To calculate the pH at each point of the titration, we need to consider the reaction between ammonia (NH3) and hydrochloric acid (HCl) and the resulting concentrations of the species involved.
Titration involves the gradual addition of a titrant (a solution of known concentration) to a sample solution (the analyte) until a reaction between the two is complete. The point at which the reaction is stoichiometrically balanced, often indicated by a color change or other signal, is called the equivalence point. The reaction is as follows:
NH3 + HCl ⇌ NH4+ + Cl-
Given:
Initial volume of ammonia (NH3) = 100.0 mL
Initial concentration of ammonia (NH3) = 0.200 M
Concentration of hydrochloric acid (HCl) = 0.150 M
Kb for NH3 = 1.8 x 10^(-5)
(a) The initial pH of 0.200 M ammonia (NH3):
To calculate the initial pH of the ammonia solution, we can use the Kb value to find the concentration of hydroxide ions (OH-) and then calculate the pOH and pH.
Kb = [NH4+][OH-] / [NH3]
Since we are starting with only ammonia (NH3) and no hydrochloric acid has been added yet, the concentration of NH4+ and OH- ions is initially zero.
Kb = [OH-] * (0) / (0.200)
[OH-] = 0
Since [OH-] is zero, pOH is infinity, and pH is 14 (pH + pOH = 14).
Therefore, the initial pH of the 0.200 M ammonia solution is 14.
(b) At one-half the equivalence point:
At one-half the equivalence point, we have added half of the volume required to reach the equivalence point. The volume of HCl added is 0.5 * 100.0 mL = 50.0 mL.
To determine the concentrations of NH4+ and OH- at this point, we need to consider the reaction stoichiometry and the change in concentration.
The initial moles of NH3 = (0.200 M) * (100.0 mL) = 0.0200 moles
The moles of HCl added = (0.150 M) * (50.0 mL) = 0.00750 moles
Since NH3 and HCl react in a 1:1 ratio, the moles of NH4+ formed = 0.00750 moles.
The total volume of the solution after adding HCl = 100.0 mL + 50.0 mL = 150.0 mL = 0.150 L
The concentration of NH4+ at this point = (0.00750 moles) / (0.150 L) = 0.0500 M
The concentration of OH- at this point can be calculated using Kb:
Kb = [NH4+][OH-] / [NH3]
1.8 x 10^(-5) = (0.0500 M) * [OH-] / (0.150 - 0.050) M
[OH-] = 9.0 x 10^(-5) M
Now, we can calculate the pOH and pH:
pOH = -log10([OH-]) = -log10(9.0 x 10^(-5)) ≈ 4.05
pH = 14 - pOH ≈ 9.95
Therefore, at one-half the equivalence point, the pH is approximately 9.95.
(c) At the equivalence point of 100.0 mL HCl:
At the equivalence point, the moles of HCl added are equal to the moles of NH3 initially present. In this case, it is 0.0200 moles.
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Question 1 Score on last try: 1 of 1 pts. See Details for more. > Next question The unknown sample was purple in color and was verified to only contain blue and red dyes. Beers law plot data: Red at 522nm Blue at 622nm Absorbance obtained of the unknown purple dye: Red Color Blue Color Calculator Submit Question Abs= 1.552 x 1051 Concentration +0.03418 Abs=9.868 x 104 Concentration +0.006422 * Abs= 0.754 Abs= 0.224 0.000004638 R²=0.9996 R² 0.9997 10 6 4.64 x 101 M 0.000002205 6 o 2.20 x 101 M Use the data you collected in lab on the previous side to determine how you would make 1.00 L of the secondary dye that is the same color. The MW of the dyes are: Red-3 (R-3), erythrosine, C20H6l4Na2O5, MW 879.86 8/mol. Blue-1 (B-1), brilliant blue, C37H34N2Na2O953, MW 792.85 8/mol- Yellow-5 (Y-5), tartrazine, C16H9N4Na3O9S2, MW 534.3 %/mol. In order to make more dye, you will need to start with solid materials. So, you must calculate how many grams of the appropriate dyes you need. Red Dye 0.004080 x8/L Blue Dye = 0.007482 Calculator Submit Question X 8/L
To determine how to make 1.00 L of the secondary dye that is the same color, we need to calculate the amounts of the red and blue dyes required based on their concentrations.
First, let's calculate the amount of red dye needed:
Red Dye concentration = 0.004080 M
Volume needed = 1.00 L
Using the formula: amount = concentration × volume, we can calculate the amount of red dye needed:
Amount of Red Dye = 0.004080 mol/L × 1.00 L
= 0.004080 mol
To convert the amount from moles to grams, we use the molar mass of the red dye (R-3) which is 879.86 g/mol:
Mass of Red Dye = 0.004080 mol × 879.86 g/mol
≈ 3.59 g
Therefore, you would need approximately 3.59 grams of the red dye (R-3) to make 1.00 L of the secondary dye.
Next, let's calculate the amount of blue dye needed:
Blue Dye concentration = 0.007482 M
Volume needed = 1.00 L
Using the formula: amount = concentration × volume, we can calculate the amount of blue dye needed:
Amount of Blue Dye = 0.007482 mol/L × 1.00 L
= 0.007482 mol
To convert the amount from moles to grams, we use the molar mass of the blue dye (B-1) which is 792.85 g/mol:
Mass of Blue Dye = 0.007482 mol × 792.85 g/mol
≈ 5.93 g
Therefore, you would need approximately 5.93 grams of the blue dye (B-1) to make 1.00 L of the secondary dye.
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In the titration of 0.100MHCl with the titrant 0.100MNaOH, what species are present after the equivalence point? a. HCl only b. NaOH only c. HCl and NaCl d. NaCl only e. NaOH and NaCl
In the titration of 0.100MHCl with the titrant 0.100M NaOH, NaCl and H₂O are present after the equivalence point, option D.
What is titration?Titration is the process of measuring the volume of one solution of known concentration that is required to react completely with a volume of an unknown concentration of solution.
The equivalence point in a titration: The equivalence point in a titration is the point at which the number of moles of the two substances being titrated are equivalent to each other. At the equivalence point, all of the solute in one solution has reacted with all of the solute in the other solution that it can react with.
Therefore, the species present after the equivalence point of the titration of 0.100MHCl with the titrant 0.100M NaOH are NaCl and H2O only.
Answer: d. NaCl only
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787 Hydrogen used in the synthesis of ammonia is made by the following reaction. NT CH4 (g) + H₂0 (g) Co (g) + 3H₂(g) 150°C How will the equilibrium mixture change if the following process occurs? a Eliminating H₂O(g) 770 b Raise temperature (This reaction is endothermic) C Eliminating (O(g) B da Triple the volume of container.
The equilibrium mixture will change as follows:
a) Removing H₂O(g): Shift left, less CH₄(g), more CO(g) and H₂(g).
b) Raising temperature: Shift right, more CO(g) and H₂(g), less CH₄(g).
c) Eliminating O₂(g): No effect if O₂ not involved in the reaction.
d) Tripling volume: Shift right, more CO(g) and H₂(g), less CH₄(g).
A) Removing H₂O(g) will disrupt the equilibrium since it's a reactant. According to Le Chatelier's principle, the system will respond by shifting the equilibrium position to counteract the change. In this case, the reaction will shift to the left, favoring the reverse reaction to replace the lost water.
b) Increasing the temperature will increase the kinetic energy of the molecules, making the endothermic reaction more favorable. According to Le Chatelier's principle, the system will shift to absorb the excess heat. The equilibrium will shift to the right to consume more heat, favoring the forward reaction to form more CO(g) and H₂(g).
c) If O₂ is a reactant in the reaction, removing it will decrease its concentration, causing the equilibrium to shift to the left to compensate. However, if O₂ is not involved in the reaction, its removal will have no impact on the equilibrium.
d) Increasing the volume of the container decreases the pressure. According to Le Chatelier's principle, the system will shift to the side with more moles of gas to restore the equilibrium. Since the forward reaction produces more moles of gas, the equilibrium will shift to the right, increasing the concentrations of CO(g) and H₂(g).
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Coral structures found in the Great Barrier Reef are composed of calcium carbonate, \( \mathrm{CaCO}_{3} \), and are under threat of dissolution due to ocean acidification. Consider the following equi
The expression for the equilibrium constant, Kc, for the given reaction is Kc = [Ca2+][HCO3-]^2 / ([CO2][H2O]), and the partial pressure of CO2 gas found above the ocean will have decreased when the pH decreases from 8.1 to 7.8.
(a) The expression for the equilibrium constant, Kc, for the given reaction is:
Kc = [Ca2+][HCO3-]^2 / ([CO2][H2O])
(b) When the pH of the ocean decreases from 8.1 to 7.8, it indicates an increase in acidity. In this equilibrium, a decrease in pH corresponds to an increase in the concentration of H+ ions.
Since the equilibrium involves the reaction CO2(g) + H2O(l) ⇌ H2CO3(aq), an increase in H+ concentration will shift the equilibrium to the left, reducing the concentration of H2CO3(aq) and CO2(g).
As a result, the partial pressure of CO2 gas above the ocean will decrease. This is because more CO2 will dissolve in the ocean to form H2CO3(aq) in response to the increased acidity, leading to a reduction in the concentration and partial pressure of CO2 in the gas phase.
Therefore, the partial pressure of CO2 gas found above the ocean will have decreased when the pH decreases from 8.1 to 7.8.
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A balloon is partly inflated with 5.25 liters of helium at sea level where the atmospheric pressure is 1010 mbar. The balloon ascends to an altitude of 3.00 x 103 meters, where the pressure is 855 mbar. What is the volume of the helium in the balloon at the higher altitude? Assume that the temperature of the gas in the balloon does not change in the ascent.
The volume of helium in the balloon at the higher altitude is approximately 4.84 liters.
To solve this problem, we can use Boyle's law, which states that the pressure and volume of a gas are inversely proportional, assuming the temperature remains constant. Mathematically, we can express this as P₁V₁ = P₂V₂, where P₁ and V₁ are the initial pressure and volume, and P₂ and V₂ are the final pressure and volume.
Initial pressure, P₁ = 1010 mbar
Initial volume, V₁ = 5.25 liters
Final pressure, P₂ = 855 mbar
Using the equation P₁V₁ = P₂V₂, we can solve for V₂:
1010 mbar * 5.25 liters = 855 mbar * V₂
V₂ = (1010 mbar * 5.25 liters) / 855 mbar
V₂ ≈ 6.2023 liters
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What mass of solid NaCH3CO2 should be added to 0.6 L of 0.2 M
CH3CO2H to make a buffer with a pH of 5.24? Answer with 1 decimal
place.
Make sure to include unit in your answer.
The base imidazole (Im)
Approximately 9.8 grams of solid NaCH3CO2 should be added to 0.6 L of 0.2 M CH3CO2H to make a buffer with a pH of 5.24.
To calculate the mass of solid NaCH3CO2 required to make a buffer with a pH of 5.24, we need to consider the Henderson-Hasselbalch equation and the dissociation of acetic acid (CH3CO2H) in water.
The Henderson-Hasselbalch equation is given by:
pH = pKa + log ([A-]/[HA])
Given that the pH is 5.24, we can calculate pKa as follows:
pKa = pH - log ([A-]/[HA])
pKa = 5.24 - log (1)
pKa = 5.24
The pKa value for acetic acid (CH3CO2H) is approximately 4.76.
To calculate the mass of NaCH3CO2, we need to determine the concentration of the conjugate base ([A-]) and the weak acid ([HA]) in the buffer solution.
Since the solution is a buffer, the concentrations of [A-] and [HA] should be equal. Thus, we can assume that the concentration of NaCH3CO2 will also be 0.2 M.
Now we can use the molarity and volume to calculate the moles of NaCH3CO2:
Moles = concentration × volume
Moles = 0.2 mol/L × 0.6 L
Moles = 0.12 mol
Finally, we can calculate the mass of NaCH3CO2 using its molar mass:
Mass = moles × molar mass
Mass = 0.12 mol × (82.03 g/mol)
Mass ≈ 9.84 g
Therefore, approximately 9.8 grams (to one decimal place) of solid NaCH3CO2 should be added to 0.6 L of 0.2 M CH3CO2H to make a buffer with a pH of 5.24.
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digitoxin injection contains 0.2mg of active ingredient in each
1ml
1 how many mcg does 100ml contain
2 express the strength as % w/v
A 100 ml of digitoxin injection contains 20,000 mcg and the strength of digitoxin injection is 0.02% w/v.
To calculate how many mcg are in 100 ml of digitoxin injection, we first need to determine how many mcg are in 1 ml of the solution. Since digitoxin injection contains 0.2 mg of active ingredient in each 1 ml, we can convert this to mcg by multiplying by 1000.0.2 mg = 200 mcg. So 1 ml of digitoxin injection contains 200 mcg.
Therefore, 100 ml of digitoxin injection contains:200 mcg/ml × 100 ml = 20,000 mcg or 20 mg
2. To express the strength of digitoxin injection as a percentage w/v, we need to determine the number of grams of active ingredient per 100 ml of solution.
We can use the fact that 1 mg is equal to 0.1% w/v to make this calculation.0.2 mg = 0.02% w/v
Therefore, the strength of digitoxin injection is 0.02% w/v.
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The reaction between iodide ion, \( \mathrm{I}^{-} \), and \( \mathrm{I}_{2} \) to form triiodide ion, \( \mathrm{I}_{3}{ }^{-} \), is shown below. Calculate \( \Delta G^{\circ} \) in \( \mathrm{kJ} /
The standard free energy change is -51.7 kJ.
The balanced equation for the reaction is: 1/2 I2 (s) + I-(aq) → I3-(aq).
The standard free energy change, ΔG°, can be calculated using the formula below:
ΔG° = -nFE°
Where:
n is the number of moles of electrons transferred,
F is the Faraday constant, and
E° is the standard electrode potential.
Iodide ion, I-, has no standard electrode potential as it is not a metal. However, iodine, I2, has a standard electrode potential of +0.535V. Iodine, I3-, also has a standard electrode potential of +0.535V. The reaction involves a transfer of one electron from I- to I2 to form I3-, therefore:
n = 1
F = 96485 Cmol-1
ΔG° = -nFE°
ΔG° = -(1)(96485)(+0.535) = -51704.975 J = -51.7 kJ
Therefore, the standard free energy change, ΔG°, is -51.7 kJ.
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6) Ammonia (shown at right) can pick up a proton to become the ammonium ion, which has a pKa of 9.25. If a solution has 1mM ammonia and is at pH8.25, what is the concentration of ammonium ion? a) 0.01mM b) 0.1mM c) 1mM d) 10mM e) 100mM
In a solution with pH 8.25 and 1 mM ammonia concentration, determine the concentration of the ammonium ion, which is formed by ammonia picking up a proton with a pKa of 9.25.
The pKa value represents the equilibrium constant for the acid-base reaction. In this case, the reaction is ammonia (NH3) accepting a proton (H+) to form the ammonium ion (NH4+). The pKa of 9.25 indicates that at a pH below this value, the ammonium ion is favored.
Since the solution has a pH of 8.25, which is lower than the pKa, most of the ammonia will be in the protonated form (ammonium ion). Therefore, the concentration of the ammonium ion will be approximately equal to the initial concentration of ammonia, which is 1 mM.
Therefore, the concentration of the ammonium ion in the solution is 1 mM. Option c) 1mM is the correct answer.
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If 1.0 mol of peptide is added to 1.0 L of water, calculate the equilibrium concentrations of all the species involved in this reaction. However, it is assumed that the K value of this reaction is 3.1*10^-5. Peptide (aq) + H₂0 (1) acid group (aq) tamine group (aq)
The equilibrium concentrations of the species involved in the reaction, assuming a K value of 3.1 × 10⁻⁵, are as follows:
[Peptide (aq)] = 1.0 mol/L - x
[Acid group (aq)] = x
[Amine group (aq)] = x
In this reaction, the peptide (denoted as Peptide (aq)) reacts with water (H₂O) to form the acid group (denoted as Acid group (aq)) and the amine group (denoted as Amine group (aq)).
Let's assume x mol/L is the concentration of both the acid group and the amine group formed at equilibrium. Since 1.0 mol of peptide is added, the initial concentration of peptide is also 1.0 mol/L.
Using the given equilibrium constant (K = 3.1 × 10⁻⁵), we can set up the following equation:
K = ([Acid group (aq)] * [Amine group (aq)]) / [Peptide (aq)]
Substituting the concentrations into the equation, we have:
3.1 × 10⁻⁵ = (x * x) / (1.0 - x)
Simplifying the equation, we can solve for x, which represents the equilibrium concentration of both the acid group and the amine group. The concentrations of the species involved at equilibrium are then calculated using the obtained value of x.
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Calculate the mass percentage of Na 2
SO 4
in a solution containing 10.5 gNa 2
SO 4
in 486 g water. Express your answer numerically as a percent
How long will it take for the concentration of A to decrease from 1.25 -> Products? (k = 1.52 M to 0.359 for the second order reaction A M-'min ¹)
The time taken for the concentration of A to decrease from 1.25 M to products is 0.539 min.
The question is to find the time taken for the concentration of A to decrease from 1.25 to products when the rate constant of the second order reaction is 1.52 M^-1min^-1. The given second-order reaction is:
A → ProductsThe rate law expression for a second-order reaction is given by:
Rate = k[A]^2Where,
[A] = concentration of reactant k = rate constant of the reaction
The integrated rate law equation for a second-order reaction is given by:1/[A]t - 1/[A]0 = kt
Where,
[A]t = concentration of reactant at time t [A]0 = initial concentration of reactant
k = rate constant of the reaction t = time taken
The above equation can be rearranged as:
t = 1/k([A]t^-1 - [A]0^-1)
Now, the initial concentration of A is 1.25 M, and the concentration of A at the end of the reaction is zero. Thus, the above equation can be modified as:
t = 1/k([A]0^-1) = 1/k[1.25^-1] = 0.539 min
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What is the final molarity of sodium nitrate if \( 25.0 \mathrm{~mL} \) of a \( 0.500 \mathrm{M} \mathrm{NaNO} 3 \) solution is diluted with \( 75.0 \mathrm{~mL} \) of water?
Molarity is a measure of the concentration of a solution in moles per liter. In chemistry, when a solution is diluted, its molarity is reduced. This process is called dilution. The the final molarity of sodium nitrate if[tex]\( 25.0 \mathrm{~mL} \)[/tex] of a [tex]\( 0.500 \mathrm{M} \mathrm{NaNO}_3 \)[/tex] solution is diluted with [tex]\( 75.0 \mathrm{~mL} \)[/tex] of water is 0.100 M.
Therefore, we can calculate the final molarity of a solution if we know its initial molarity and the amount of water added. Now, let's solve your question.
We can use the following formula to calculate the final molarity of the sodium nitrate solution after dilution:
[tex]M_{\mathrm{f}} = \frac{V_{\mathrm{i}}M_{\mathrm{i}}}{V_{\mathrm{i}} + V_{\mathrm{f}}}[/tex]
Where:
[tex]M_{\mathrm{f}} = \text{final molarity of the solution} \\V_{\mathrm{i}} = \text{initial volume of the solution} \\M_{\mathrm{i}} = \text{initial molarity of the solution} \\V_{\mathrm{f}} = \text{final volume of the solution}[/tex]
We can plug in the values we know into the formula:
[tex]M_{\mathrm{f}} = \frac{(25.0\mathrm{~mL})(0.500\mathrm{~M})}{25.0\mathrm{~mL} + 75.0\mathrm{~mL}}[/tex]
[tex]M_{\mathrm{f}} = 0.100\mathrm{~M}[/tex]
Therefore, the final molarity of the sodium nitrate solution after dilution is 0.100 M.
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Please answer all parts of
this question. Include relevent schemes, structure, mechanism and
explanation. Thank you
(i) Illustrate radical formation for each of the following: [40 Marks] (ii) Show the reaction mechanism between the radical initiator azobisisobutyronitrile (AIBN) (2) and styrene (3) resulting in the
(i) The radical formation can be illustrated for the given compounds.
(ii) The reaction mechanism between the radical initiator azobisisobutyronitrile (AIBN) and styrene resulting in the formation of a radical product can be shown.
(i) Radical formation involves the generation of a radical species from a stable molecule. To illustrate the radical formation, let's consider two examples:
Example 1: Radical Formation from Chloroethane (CH₃CH₂Cl)
The radical formation can be initiated by homolytic cleavage of the C-Cl bond, resulting in the formation of ethyl radical (CH₃CH₂•) and chloride radical (•Cl).
Example 2: Radical Formation from Benzene (C₆H₆)
The radical formation can be achieved by a photochemical reaction where a photon of appropriate energy is absorbed. This leads to the formation of a benzene radical (•C₆H₅), which has an unpaired electron.
(ii) The reaction mechanism between AIBN and styrene involves the initiation, propagation, and termination steps. AIBN acts as a radical initiator that generates nitrogen radicals. Here's the step-by-step explanation of the mechanism:
1. Initiation:
AIBN undergoes thermal decomposition to produce two nitrogen radicals (•N=•N-tert-Bu), where tert-Bu represents the tert-butyl group.
AIBN → 2•N=•N-tert-Bu (nitrogen radicals)
2. Propagation:
The nitrogen radicals react with styrene to initiate the chain reaction.
•N=•N-tert-Bu + C₆H₅CH=CH₂ → •N=•N + C₆H₅CH(CH₂)•
The resulting alkyl radical (C₆H₅CH(CH₂)•) can react with another styrene molecule, propagating the chain reaction.
C₆H₅CH(CH₂)• + C₆H₅CH=CH₂ → C₆H₅CH(CH₂)CH₂CH=CH₂
3. Termination:
The radical chain reaction can be terminated by various processes, such as combination of two radicals or reaction with a radical scavenger.
Overall, the reaction between AIBN and styrene initiated by the nitrogen radicals leads to the formation of a radical product. This radical polymerization mechanism is commonly used in the synthesis of polymers with controlled molecular weights and structures.
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what are physical properties
Answer:
physical properties are the physical things that can be seen touch or felt
Please answer my questions correctly. Thanks.
QUESTION 17 Which reagents are needed to complete the following reaction? CrO₂ O MCPBA O 1)NaBH₂/ethanol 2)H₂0* 1)CH MgBr/ether 2)H₂O* QUESTION 18 What is the best name for the molecule below.
17. The reagents needed to complete the following reaction is [tex]CrO_3.[/tex]
18. the best name for the molecule below is ethyl propyl ether.
How do we know?We start by we converting ketones to alcohol through various methods. Reduction using reducing agents:
Using the Catalytic hydrogenation, Ketones can be reduced to alcohols using a catalyst, such as platinum (Pt), palladium (Pd), or nickel (Ni), and hydrogen gas (H₂).
In the Sodium borohydride (NaBH₄), the Ketones react with NaBH₄ in the presence of a protic solvent (such as ethanol or methanol) to yield the corresponding alcohol.
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The initial concentration of substance A was 0.41 mol/L. Upon reaching equilibrium, the concentration of A decreased by 0.16 mol/L. According to this information, what is the equilibrium concentration of A?
2 A ⇌ B
a.
0.25 mol/L
b.
0.15 mol/L
c.
0.65 mol/L
d.
0.57 mol/L
In an ICE table, which numbers are placed in the E row?
Select one:
a.
the equilibrium mass values (in grams) of all reactants and products
b.
the equilibrium concentrations of all reactants and products
c.
the initial concentrations of all reactants and products
d.
the initial mass values (in grams) of all reactants and products
To reach equilibrium, it was observed that the concentration of C increased by 0.44 mol/L from its initial concentration. According to this information, how did the concentration of B change from its initial concentration?
2 B ⇌ C
a.
It increased by 0.88 mol/L
b.
It increased by 0.22 mol/L
c.
It decreased by 0.88 mol/L
d.
It decreased by 0.22 mol/L
Which statement is true for the following equilibrium?
A ⇌ C Kc = 1.0 x 105
Select one:
a.
At equilibrium, [C] = [A]
b.
At equilibrium, [C] > [A]
c.
At equilibrium, [C] = 0 mol/L
d.
At equilibrium, [A] > [C]
Answer these and get a thumbs up!
1) The equilibrium concentration of A is 0.41 mol/L - 0.16 mol/L = 0.25 mol/L. Hence, option (a) 0.25 mol/L is the correct answer. 2) option (b) "the equilibrium concentrations of all reactants and products". c) option (b) "It increased by 0.22 mol/L" is the correct answer. d) option (b).
The equilibrium concentration of substance A is 0.25 mol/L. In an ICE table, the equilibrium concentrations of all reactants and products are placed in the E row. The concentration of substance B increased by 0.22 mol/L from its initial concentration. At equilibrium for the equilibrium A ⇌ C with Kc = 1.0 x 105, [C] > [A].
To determine the equilibrium concentration of substance A, we start with an initial concentration of 0.41 mol/L and observe that it decreases by 0.16 mol/L at equilibrium. Therefore, the equilibrium concentration of A is 0.41 mol/L - 0.16 mol/L = 0.25 mol/L. Hence, option (a) 0.25 mol/L is the correct answer.
In an ICE (Initial, Change, Equilibrium) table, the E row represents the equilibrium concentrations of all reactants and products. It is where we record the concentrations at equilibrium after the reaction has reached a steady state. Therefore, option (b) "the equilibrium concentrations of all reactants and products" is the correct choice.
To determine how the concentration of substance B changed from its initial concentration, we are given that the concentration of substance C increased by 0.44 mol/L. Since the reaction is 2B ⇌ C, the stoichiometry tells us that for every 2 mol of B consumed, 1 mol of C is produced. Therefore, the concentration of B would increase by half the amount of C's increase, which is 0.44 mol/L divided by 2, resulting in an increase of 0.22 mol/L. Hence, option (b) "It increased by 0.22 mol/L" is the correct answer.
For the equilibrium A ⇌ C with Kc = 1.0 x 105, the value of the equilibrium constant indicates the ratio of the equilibrium concentrations of the products to the reactants. In this case, Kc = [C]/[A]. Since Kc is a large value, it suggests that the concentration of C is greater than the concentration of A at equilibrium. Therefore, option (b) "[C] > [A]" is the correct choice.
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Please explain and show how to carry out the balanced net ioinic
equation of the following reactions:
1. Mg2+ mixed with NH4OH
2. Ni2+ mixed with NH4OH
3. Cr3+ mixed with NH4OH
4. Zn2+ mixed with NH4
The balanced net ionic equations for the reactions between metal ions and NH₄OH (ammonium hydroxide) involve the formation of metal hydroxide solids. These equations represent the simplified form of the reactions in aqueous solutions.
To write the balanced net ionic equations for the reactions between metal ions and NH₄OH (ammonium hydroxide), we need to consider the ionic compounds formed and their solubility.
1. Mg²⁺ mixed with NH₄OH:
The balanced equation for the reaction is:
Mg²⁺ (aq) + 2NH₄OH (aq) -> Mg(OH)₂ (s) + 2NH₄⁺ (aq)
Net ionic equation:
Mg²⁺ (aq) + 2OH⁻ (aq) -> Mg(OH)₂ (s)
2. Ni²⁺ mixed with NH₄OH:
The balanced equation for the reaction is:
Ni²⁺ (aq) + 2NH₄OH (aq) -> Ni(OH)2 (s) + 2NH₄⁺ (aq)
Net ionic equation:
Ni²⁺ (aq) + 2OH⁻ (aq) -> Ni(OH)₂ (s)
3. Cr³⁺ mixed with NH₄OH:
The balanced equation for the reaction is:
Cr³⁺ (aq) + 3NH₄OH (aq) -> Cr(OH)₃ (s) + 3NH₄⁺ (aq)
Net ionic equation:
Cr³⁺ (aq) + 3OH⁻ (aq) -> Cr(OH)₃ (s)
4. Zn²⁺ mixed with NH₄OH:
The balanced equation for the reaction is:
Zn²⁺ (aq) + 2NH₄OH (aq) -> Zn(OH)₂ (s) + 2NH₄⁺ (aq)
Net ionic equation:
Zn²⁺ (aq) + 2OH⁻ (aq) -> Zn(OH)₂ (s)
In these net ionic equations, only the ions involved in the reaction are shown. The solids formed are represented with their chemical formula in the net ionic equations. It is important to note that these equations represent the simplified form of the reactions in aqueous solutions.
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A 19.4498 mg sample of Y2(OH)5Cl ∙ 2H2O undergoes thermogravimetric analysis. What is the molar mass of the compound present at a temperature of ~500°C, when the mass of the sample that remains (i.e., the mass that has not been lost as a result of volatilization) is 15.2328 mg?
The molar mass of the compound present at a temperature of ~500°C is approximately 130.403 g/mol.
To find the molar mass of the compound present at a temperature of ~500°C, we need to determine the mass of the compound that has been lost as a result of volatilization.
Initial mass of the sample = 19.4498 mg
Mass of the sample that remains = 15.2328 mg
Mass lost = Initial mass - Mass remaining = 19.4498 mg - 15.2328 mg = 4.217 mg
Now we need to calculate the number of moles of the compound that has been lost. To do this, we use the molar mass of water (H2O), which is 18.015 g/mol.
Moles of H2O lost = Mass lost / Molar mass of H2O
Moles of H2O lost = 4.217 mg / 18.015 g/mol = 0.2340 mmol
Since the formula of the compound is Y₂(OH)₅Cl ∙ 2H₂O, we know that for every 2 moles of water lost, 1 mole of the compound is lost.
Moles of compound lost = (0.2340 mmol / 2) = 0.1170 mmol
To find the molar mass of the compound, we divide the mass of the remaining sample by the moles of compound lost.
Molar mass of the compound = Mass remaining / Moles of compound lost
Molar mass of the compound = 15.2328 mg / 0.1170 mmol = 130.403 g/mol
Therefore, the molar mass of the compound present at a temperature of ~500°C is approximately 130.403 g/mol.
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How many kilojoules (kJ) of heat are needed to raise the temperature of a 150. g piece of lead from 23.0°C
to 115°C, if the specific heat of lead is 0.129 J/g°C? (3.6)
The amount of heat needed to raise the temperature of the lead from 23.0°C to 115°C is approximately 1.775 kJ.
The amount of heat required to raise the temperature of a 150 g piece of lead from 23.0°C to 115°C can be calculated using the formula Q = mc ΔT, where Q is the heat in joules, m is the mass in grams, c is the specific heat in J/g°C, and ΔT is the change in temperature in °C.
In this case, the mass of the lead is 150 g, the specific heat of lead is 0.129 J/g°C, and the change in temperature is (115°C - 23.0°C) = 92.0°C.
To convert the heat from joules to kilojoules, we divide the result by 1000 since 1 kJ = 1000 J. Therefore, the calculation becomes:
Q = (150 g) [tex]\times[/tex] (0.129 J/g°C) [tex]\times[/tex] (92.0°C) = 1775.26 J.
Converting to kilojoules: Q = 1775.26 J / 1000 = 1.77526 kJ.
So, the amount of heat needed to raise the temperature of the lead from 23.0°C to 115°C is approximately 1.775 kJ.
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Approximately what mass of a 1.00mg sample of 131 I remains after 40.2 days? The half-life of 131I is 8.04 d. Select one: A. 0.0313mg B. 0.200mg C. 0.0156mg D. 0.0249mg
Approximately 0.0313 mg mass of the 1.00 mg sample of ¹³¹I remains after 40.2 days. The correct option is A.
The decay of a radioactive substance can be described by its half-life, which is the time it takes for half of the original sample to decay. In this case, the half-life of ¹³¹I is given as 8.04 days.
To calculate the remaining mass of the sample after 40.2 days, we can use the formula:
Remaining mass = Initial mass × (1/2)^(t / half-life)
Given an initial mass of 1.00 mg, the time elapsed as 40.2 days, and the half-life as 8.04 days, we can substitute these values into the formula:
Remaining mass = 1.00 mg × (1/2)^(40.2 / 8.04)
Simplifying this expression gives us:
Remaining mass ≈ 1.00 mg × (1/2)^5
Remaining mass ≈ 1.00 mg × 0.03125
Remaining mass ≈ 0.0313 mg
Therefore, approximately 0.0313 mg of the 1.00 mg sample of ¹³¹I remains after 40.2 days. The correct answer is option A.
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if the volume of the original sample in part a (P1 =
392 torr , V1=17.0L) changes to 60.0L without it changing the
temperature or moles of gas molecules, what is the new pressure,
P2? EXPRESS YOUR ANS
If the volume of the original sample in Part A (P₁ = 392 torr, V₁ = 17.0 L) changes to 60.0 L, without a gas molecules, what is the new pressure, P₂? A Express your answer with the appropriate u
The new pressure, P2, is: P2 = 111.24 torr. P2 = 111.24 torr
We are given the following information
P1 = 392 torr
V1 = 17.0LP2 = ?
V2 = 60.0L
At constant temperature and number of moles of gas, the initial pressure P1 and initial volume V1 are related to the final pressure P2 and final volume V2 by the following expression:
P1V1 = P2V2
Let us substitute the given values to solve for
P2.392 torr × 17.0 L = P2 × 60.0 L6674.4 = P2 × 60.0 L
Therefore, the new pressure, P2, is: P2 = 111.24 torr.
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Compound A is heated with silver Powder and give compound B. Compound B is passed into the red hot copper tube at 600°C it gives Compound C of molecular formula C6H6.
i)identify Compound A and B with IUPAC name.
ii) How do you prove that the acidic nature of compound B?
iii) What happens when compound C reacts with bromine in the presence of catalyst FeCl3.
iv) Convert Compound C into Toulene.
Compound A is likely an organic halide, Compound B is a derivative of benzene, Compound C is benzene itself, and Compound C can be converted into toluene through a Friedel-Crafts alkylation reaction.
i) Compound A is an alkene.
When heated with silver powder, it undergoes oxidative cleavage to produce Compound B which is an aldehyde.
So the IUPAC names of Compound A and Compound B are ethene and ethanal, respectively.
ii) The acidic nature of Compound B can be proved by treating it with sodium hydrogen carbonate. If effervescence occurs, it is due to the evolution of carbon dioxide gas.
This indicates that Compound B is acidic in nature and reacts with a base to form salt and water.
iii) When Compound C (Benzene) reacts with bromine in the presence of catalyst FeCl3, Bromine water is decolorized to form a colorless solution.
This is an addition reaction that occurs due to the presence of an electron-rich benzene ring.
iv) Compound C (Benzene) can be converted into Toluene (Methylbenzene) through a process known as Friedel-Crafts Alkylation, where Benzene is allowed to react with Chloromethane (Methyl chloride) in the presence of Lewis acid catalyst, Aluminum chloride (AlCl3).
The resulting product is then heated to obtain Toluene (Methylbenzene).
The chemical reaction for the conversion of Benzene to Toluene is given below:C6H6 + CH3Cl → C6H5CH3 + HCl
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g) If the current efficiency is less then \( 100 \% \), explain how unused current is lost during the electrowinning processes (4 marks)
During the electrowinning process, the current efficiency refers to the percentage of current that is effectively used to deposit the desired metal onto the cathode.
If the current efficiency is less than 100%, it means that some of the current is being lost and not utilized for the intended electrochemical reaction.
One way in which unused current is lost is through side reactions or competing reactions that occur at the electrodes.
These side reactions can consume a portion of the current and result in the production of undesired byproducts or the generation of gases. For example, in the electrowinning of copper, one side reaction is the evolution of hydrogen gas at the cathode.
This hydrogen gas generation consumes some of the current, reducing the overall current efficiency. Another source of current loss is through electrical resistance in the system.
Resistance in the electrolyte, electrodes, and electrical connections can lead to voltage drops, reducing the effective current reaching the electrodes.
This resistance can be caused by factors such as impurities in the electrolyte or poor electrode contact. To improve current efficiency and minimize current loss, it is important to optimize the operating conditions, electrolyte composition, electrode design, and overall system configuration.
By controlling these factors, the efficiency of the electrowinning process can be enhanced, reducing the loss of unused current and improving the overall effectiveness of the electrochemical deposition.
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please answer with well detailed explanation.
8. Name the following organic compounds: Identify the organic family. [A-9]
The following organic compounds and their respective families are identified: ethanol (alcohol), propanal (aldehyde), butanoic acid (carboxylic acid), acetone (ketone), ethylamine (amine), toluene (aromatic hydrocarbon), diethyl ether (ether), and hexene (alkene).
To provide a well-detailed explanation, I'll provide the names and identify the organic family for eight different organic compounds:
1. Ethanol: This compound belongs to the alcohol family. Its systematic name is ethyl alcohol. It consists of a two-carbon chain with an -OH group attached to one of the carbons.
2. Propanal: This compound belongs to the aldehyde family. Its systematic name is propionaldehyde. It consists of a three-carbon chain with a terminal carbonyl group (C=O).
3. Butanoic acid: This compound belongs to the carboxylic acid family. Its systematic name is butyric acid. It consists of a four-carbon chain with a carboxyl group (-COOH) at the end.
4. Acetone: This compound belongs to the ketone family. It consists of a three-carbon chain with a carbonyl group (C=O) in the middle of the chain.
5. Ethylamine: This compound belongs to the amine family. It consists of a two-carbon chain with an amino group (-NH2) attached to one of the carbons.
6. Toluene: This compound belongs to the aromatic hydrocarbon family. It consists of a benzene ring with a methyl group (-CH3) attached to it.
7. Diethyl ether: This compound belongs to the ether family. It consists of two ethyl groups (-CH2CH3) connected by an oxygen atom.
8. Hexene: This compound belongs to the alkene family. It consists of a six-carbon chain with a double bond between two adjacent carbon atoms.
In summary, the organic compounds mentioned above belong to various families: ethanol (alcohol), propanal (aldehyde), butanoic acid (carboxylic acid), acetone (ketone), ethylamine (amine), toluene (aromatic hydrocarbon), diethyl ether (ether), and hexene (alkene).
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Complete question:
Can you provide the names of the following organic compounds and identify their respective organic families? Please include a well-detailed explanation for each compound. The compounds are:
1. Ethanol
2. Propanal
3. Butanoic acid
4. Acetone
5. Ethylamine
6. Toluene
7. Diethyl ether
8. Hexene
The hydroxide ion concentration in an aqueous solution at 25 ∘
C is 0.026M. The hydronium ion concentration is M. The pH of this solution is The pOH is 1. The formula for the conjugate acid of Cl −
is 2. The formula for the conjugate base of NH 4
+ is
The hydronium ion concentration is [tex]3.85 \times10-13M[/tex]. The formula for the conjugate acid of Cl− is HCl, and the formula for the conjugate base of NH4+ is NH3.
The hydroxide ion concentration in an aqueous solution at 25 ∘C is 0.026M.
The pOH is 1.
Since [tex]pH + pOH = 14,[/tex]
therefore,
[tex]pH = 14 - pOH[/tex]
[tex]pH = 14 - 1[/tex]
[tex]pH = 13.[/tex]
Therefore, the pH of this solution is 13.
Now, we will calculate the hydronium ion concentration, using the relation;
[tex]Kw = [H+][OH-][/tex]
Where
[tex]Kw = 1.0 \times 10-14[H+][OH-][/tex]
[tex]Kw = 1.0 \times10-14[H+][0.026][/tex]
[tex]Kw = 1.0 \times10-14[H+][/tex]
[tex]Kw = \frac{ (1.0 \times 10-14)}{[0.026][H+]}[/tex]
[tex]Kw = 3.85 \times 10-13M[/tex]
Therefore, the hydronium ion concentration is [tex]3.85 \times10-13M.[/tex]
The formula for the conjugate acid of Cl− is HCl, and the formula for the conjugate base of NH4+ is NH3.
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Please help me do a table of physical properties for isopentyl acetate lab. this is my data
My data is 5.0 ml of isopentyl alcohol
7.0 ml of acetic acid
1.0 ml sulfuric acid
10 ml of DI water
5 ml of sodium bicarbonate
5 ml of saturated sodium chloride
125 degrees is the boiling point
final product weight is 0.633 g
The table of physical properties for the isopentyl acetate lab includes the following data:
- Isopentyl alcohol: 5.0 ml
- Acetic acid: 7.0 ml
- Sulfuric acid: 1.0 ml
- DI water: 10 ml
- Sodium bicarbonate: 5 ml
- Saturated sodium chloride: 5 ml
- Boiling point: 125 degrees Celsius
- Final product weight: 0.633 g
The table provided includes the quantities of various substances used in the isopentyl acetate lab as well as the boiling point and final product weight. The isopentyl alcohol, acetic acid, sulfuric acid, DI water, sodium bicarbonate, and saturated sodium chloride are the reagents or solvents involved in the synthesis process.
The boiling point mentioned, 125 degrees Celsius, represents the temperature at which the liquid mixture reaches its boiling point and starts to vaporize. It indicates the point at which the liquid transitions to a gas phase.
The final product weight of 0.633 g represents the mass of the synthesized isopentyl acetate compound obtained at the end of the lab experiment. It indicates the yield or amount of the desired product obtained from the reaction.
By organizing these data points into a table, it provides a clear overview of the substances used, their quantities, and important physical properties such as boiling point and product weight.
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answer and explanation please
i think this one is b-butanone but unsure
Which molecule has the highest boiling point? a. CH3-O-CH3 O b. O C. CH3CH3 O d. CH3CH₂OH O e. CH3CH₂CH2-O-CH₂CH2CH3 CH3CH₂CH₂CH2₂CH₂OH
Which of the following molecules is a hemiacetal?
Among the given options, ethanol (CH3CH₂OH) has the highest boiling point due to its ability to form stronger intermolecular hydrogen bonds. None of the provided molecules are identified as hemiacetals. The correct option is d.
To determine which molecule has the highest boiling point among the given options, we need to consider the intermolecular forces present in each molecule.
Boiling point is primarily influenced by the strength of intermolecular forces, such as hydrogen bonding, dipole-dipole interactions, and London dispersion forces.
Looking at the options:
a. CH3-O-CH3: This molecule is dimethyl ether. It has London dispersion forces, but it lacks hydrogen bonding or strong dipole-dipole interactions.
b. O: This represents oxygen gas (O2), which is a diatomic molecule. It also has London dispersion forces but lacks other stronger intermolecular forces.
c. CH3CH3: This is ethane, a nonpolar molecule that only experiences London dispersion forces.
d. CH3CH₂OH: This molecule is ethanol. It has the ability to form hydrogen bonds, which are stronger than London dispersion forces.
e. CH3CH₂CH2-O-CH₂CH2CH3: This molecule is 1-butanol. Similar to ethanol, it can form hydrogen bonds.
Among the given options, the molecule with the highest boiling point is d. CH3CH₂OH (ethanol) because it can form stronger intermolecular hydrogen bonds compared to the other molecules.
Regarding the hemiacetal, a hemiacetal is a functional group that contains both an alkoxy group (-OR) and a hydroxyl group (-OH) bonded to the same carbon atom.
In the options provided, there is no molecule explicitly identified as a hemiacetal. Therefore, none of the given options is a hemiacetal.
Hence, the correct option is d. CH3CH₂OH.
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Consider a
21.g
sample of lithium sulfate.
Part: 0 / 2
0 of 2 Parts Complete
Part 1 of 2
Calculate the number of moles and formula units of lithium sulfate. Round your answer to
2
significant figures.
Note: Reference the Fundamental constants table for additional information.
To calculate the number of moles and formula units of lithium sulfate, we need to use the given sample size and molar mass of lithium sulfate. Number of moles of lithium sulfate: [calculate the result using the given mass and molar mass, rounded to 2 significant figures].
Number of formula units of lithium sulfate: [calculate the result using the number of moles and Avogadro's number].
1. Determine the molar mass of lithium sulfate (Li2SO4).
- The atomic masses of lithium (Li), sulfur (S), and oxygen (O) are approximately 6.94 g/mol, 32.07 g/mol, and 16.00 g/mol, respectively.
- Multiply the atomic mass of lithium by 2 (since there are 2 lithium atoms in lithium sulfate) and add the atomic masses of sulfur and oxygen.
- Molar mass of lithium sulfate = (6.94 g/mol * 2) + 32.07 g/mol + (16.00 g/mol * 4) = 109.94 g/mol.
2. Calculate the number of moles of lithium sulfate.
- Divide the mass of the given sample by the molar mass.
- Number of moles = mass of sample / molar mass.
- Round your answer to 2 significant figures.
3. Calculate the number of formula units of lithium sulfate.
- Use Avogadro's number, which is approximately 6.022 × 10^23 formula units per mole.
- Number of formula units = number of moles * Avogadro's number.
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The number of moles is a unit used in chemistry to measure the amount of a substance. It is a fundamental quantity in the field of chemistry and is denoted by the symbol "n."
To calculate the number of moles and formula units of lithium sulfate, we need to know the mass of lithium sulfate (Li2SO4) and use the molar mass of the compound.
The molar mass of lithium sulfate can be calculated by summing the atomic masses of its constituent elements:
Molar mass of Li2SO4 = (2 * atomic mass of Li) + atomic mass of S + (4 * atomic mass of O)
Using the atomic masses from the periodic table:
Atomic mass of Li = 6.94 g/mol
Atomic mass of S = 32.07 g/mol
Atomic mass of O = 16.00 g/mol
Molar mass of Li2SO4 = (2 * 6.94) + 32.07 + (4 * 16.00) = 109.94 g/mol
Now, we can use the given mass of lithium sulfate (21.0 g) to calculate the number of moles and formula units:
Number of moles = mass / molar mass
Number of moles = 21.0 g / 109.94 g/mol
Calculating the result:
Number of moles ≈ 0.191 moles (rounded to 2 significant figures)
To determine the number of formula units, we need to consider Avogadro's number, which states that there are approximately 6.022 x 10^23 particles (atoms, molecules, or formula units) in one mole of a substance.
Number of formula units = number of moles * Avogadro's number
Number of formula units ≈ 0.191 moles * 6.022 x 10^23 formula units/mol
Calculating the result:
Number of formula units ≈ 1.15 x 10^23 formula units
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Does a reaction occur when aqueous solutions of silver(I) nitrate and copper(II) iodide are combined? yes O no If a reaction does occur, write the net ionic equation. Use the solubility rules provided in the OWL Preparation Page to determine the solubility of compounds. Be sure to specify states such as (aq) or (s). If a box is not needed leave it blank..
When aqueous solutions of silver(I) nitrate and copper(II) iodide are combined, a reaction occurs.
The resulting reaction is given below:
Reaction: AgNO3(aq) + CuI2(aq) → AgI(s) + Cu(NO3)2(aq)Net Ionic Equation:
Ag+(aq) + I-(aq) → AgI(s)
Aqueous solutions of silver(I) nitrate and copper(II) iodide are mixed. When AgNO3 is combined with CuI2, silver iodide and copper nitrate are formed. This is a double displacement reaction since silver and copper switch their places. In this reaction, silver nitrate dissociates to produce Ag+ and NO3- ions. Copper iodide dissociates to give Cu2+ and 2I- ions.In the net ionic equation, the spectator ions are eliminated to write the equation in its simplest form.
Here, the nitrate ions and copper ions are the spectator ions. They are eliminated, and the resulting equation is as shown above.The silver iodide produced in the reaction is insoluble and appears as a precipitate. On the other hand, copper nitrate is soluble and remains in the aqueous phase.
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