Answer:
409.0 kg of sodium sulfate decahydrate will produce 4.49×10⁵ kJ
of heat energy.
Explanation:
CHECK THE COMPLETE QUESTION BELOW
To make use of an ionic hydrate for storing solar energy, you place 409.0 kg of sodium sulfate decahydrate on your house roof. Assuming complete reaction and 100% efficiency of heat transfer, how much heat (in kJ) is released to your house at night? Note that sodium sulfate decahydrate will transfer 354 kJ/mol
EXPLANATION
Here we were asked to calculate the amount of heat will be generated by 409.0 kg of sodium sulfate decahydrate at night assuming there Isa complete reaction and 100% efficiency of heat transfer in the process
The molecular weight of sodium sulfate decahydrate (H₂₀Na₂O₁₄S) is needed here, so it must be firstly calculated.
The molecular weight of sodium sulfate decahydrate (H₂₀Na₂O₁₄S)
( 1*20) + (22.98*2) + (16*14)+ (32*14)= 322.186 g/mol.
Thus 409.0 kg of H₂₀Na₂O₁₄S will have a value which is equivalent to = (409000g)/(322.186 g/mol.)
=1269.453mol of H₂₀Na₂O₁₄S.
But it was stated in the the question that per mole of H₂₀Na₂O₁₄S will transfer 354 kJ heat.
Therefore, 1269.453mol will transfer 1269.453× 354 kJ = 4.49×10⁵ kJ of heat.
Hence, 409.0 kg of sodium sulfate decahydrate will produce
4.49×10⁵ kJ of heat energy.
Real images can be projected onto a screen.
A. True
B. False
Answer:
True
Explanation:
A real image can be projected or seen on a screen but a virtual image cannot because a real image is formed when light rays coming from an object actually meet at a point after refraction through a lens while a virtual image is formed when light rays coming from an object only appear to meet at a point when produced ...
Hope this helps you, and Good luck!
Consider the addition of an electron to the following atoms from the third period. Rank the atoms in order from the most negative to the least negative electron affinity values based on their electron configurations.
Atom or ion Electron configuration
Br 1s22s22p63s23p64s23d104p5
Ge 1s22s22p63s23p64s23d104p2
Kr 1s22s22p63s23p64s23d104p6
Answer:
The ranks is
Ge: 3d10 4s2 4p2 (6 electrons in the outer shell)
Br: 3d10 4s2 4p5 (7 electrons in the outer shell)
Kr: 3d10 4s2 4p6 (8 electrons in the outer shell)
Explanation:
Electronic configuration reffers to the distribution of electrons of an atom or molecule in atomic or molecular orbitals. It gives us the understanding of the shape and energy of its electrons. The electronic configuration explain the The electron affinity or propensity to attract electrons
It Should be noted that the most stable configuration in an electronic configuration is attributed to when the last shell is full, i.e. when the last shell has 8 electrons.
When an atom is closer to reach the 8 electrons in the outer shell, then it's electron affinity big.
Considering the given three configuration of the elements above, we can see that "Br"needs requires only 1 electron to have 8 electrons in the outer shell, therefore, it is considered to have the biggest electron affinity among them which is reffers to as the LEAST NEGATIVE.
Ge: with the electronic configuration 3d10 4s2 4p2 has 6 electrons in the outer shell which means it still requires 2 electrons to complete 8 electrons in its outer shell, so it can be deducted that it posses an atom that is more negative than Br.
Kr: with the electronic configuration 3d10 4s2 4p6 which is a noble gas has 8 electrons in the outer shell cannot add more electrons to its outer shell because the 8 electrons is complete posses the least electron affinity among the three elements and it is the MOST NEGATIVE
Which process is used to make lime (calcium oxide) from limestone (calcium carbonate)?
Answer:
Explanation:
Calcium oxide is fromed by the decomopostion of CaCO3 at high temperature.
CaCO3 ------> CaO +CO2
Hope this helps you
complite the following reactions. NaOH(aq)+FeBr3(aq)→
Answer:
3NaOH+FeBr3>3NaBr+
Fe(OH)3
Explanation:
After writing the equation it has to be balanced
An unknown compound, B, has the molecular formula C7H12. On catalytic hydrogenation 1 mol of B absorbs 2 mol of hydrogen and yields 2-methylhexane. B has significant IR absorption band at about 3300 and 2200 cm-1. Which compound best represents B?
a. 5-methyl-1,3-hexadiene
b. 5-methyl-1-hexyne
c. 3-methyl-1-hexyne
d. 5-methyl-2-hexyne
e. 2-methyl-1,5-hexadiene
Answer:
B and D
Explanation:
If we use the info given we have a band a 3300 cm-1 and 2200 cm-1 this indicates that we have an alkyne functional group. Additionally, the hydrogenation of the unknown molecule will consume two moles of hydrogens this fits with the 2 pi bonds in the alkyne functional group. So, we can discard "a" and "e". The product of this hydrogenation is 2-methylhexane therefore we can discard c because the methyl group is placed on carbon 3. Structures b and d can work.
See figure 1
I hope it helps!
Calculate Keq for these reactions and predict if the equilibrium will lie to the right or to the left as written. (You may enter your answer in scientific notation, e.g. 1.0*10^-9. Enter your answer to two significant figures.) Reaction 1: + + pKa = 9 pKa = 38 Keq = Equilibrium position = _______ Reaction 2: + + pKa = 35 pKa = 25 Keq = Equilibrium position = _______
Complete Question
The complete question is shown on the first uploaded image
Answer:
For reaction 1
[tex]K_{eq} = 10^{29}[/tex]
The equilibrium position is to the right
For reaction 2
[tex]K_{eq} = 10^{-6.66}[/tex]The equilibrium position is to the left
Explanation:
Generally [tex]pKa[/tex] is mathematically evaluated as
[tex]pKa = pKa _ \ {left }} - pKa _ \ {right }}[/tex]
And equilibrium position [tex]K_a[/tex] is mathematically evaluated as [tex]K_{eq} = 10^\ {-pK_a}[/tex]
From the question we are told that
For reaction 1
[tex]pKa_\ {left}} \ = 9[/tex]
[tex]pKa_\ {right }} \ = 38[/tex]
So
[tex]pKa = 9-38[/tex]
[tex]pKa =-29[/tex]
So [tex]K_{eq} = 10^{-(-29)}[/tex]
[tex]K_a = 10^{29}[/tex]
This implies that the equilibrium position is to the right
For reaction 2
[tex]pKa_\ {left}} \ = 15.9[/tex]
[tex]pKa_\ {right }} \ = 9.24[/tex]
So
[tex]pKa = 15.9-9.24[/tex]
[tex]pKa = 6.66[/tex]
So [tex]K_{eq} = 10^{-(6.66)}[/tex]
[tex]K_{eq} = 10^{-6.66}[/tex]
This implies that the equilibrium position is to the left
What is the predicted order of first ionization energies from highest to lowest for lithium (Li), sodium (Na), potassium (K), and rubidium (Rb)?
Rb > K > Na > Li
K > Rb > Na > Li
Li > Na > K > Rb
Rb > K > Li > Na
Answer:
Li>Na>K>Rb
Explanation:
Answer:
c. Li > Na > K > Rb
Explanation:
edge 2021
(:
Classify the following as Arrhenius, Bronsted-Lowry, or Lewis acid-base reactions. A reaction may fit all, two, one, or none of the categories:I. Cu2+ + 4 Cl− CuCl42−II. Al(OH)3 + 3HNO3 Al3+ + 3H2O + 3 NO3−III. N2 + 3 H2 2NH3IV. CN− + H2O HCN + OH
Answer:
I. Lewis acid-base reaction
II. Arrhenius, Brønsted-Lowry, and Lewis' acid-base reaction
III. Brønsted-Lowry and Lewis'acid-base reaction
IV. Lewis acid-base reaction
Explanation:
According to Arrhenius, an acid is a substance that dissolves in water to produce H+ ions, and a base is a substance that dissolves in water to produce hydroxide (OH−) ions.
In the reaction below, AH is an avid, BOH is a base reacting together to form a salt(A-B+) and water only.
AH + BOH ---> A-B+ + H2O
According to Brønsted-Lowry definition, an acid is any substance that can donate a proton, and a base is any substance that can accept a proton.
In the reaction below, AH is an acid while B is a base, reacting together to form an acid-base conjugate pair.
AH + B <-----> BH+ + A-
According to Lewis' definition, an acid is a species that accepts an electron pair while a base donates an electron pair resulting in a coordinate covalently bonded compound, also known as an adduct. In the reaction below, A+ is an acid, B- is a base, reacting together to form product A-B.
A+ + B- ------> A-B
Considering the above definitions;
I. Cu²+ + 4 Cl− ---> CuCl4²− is a Lewis acid-base reaction because it involves electron sharing only.
II. Al(OH)3 + 3HNO3 ---> Al3+ + 3H2O + 3 NO3− is an Arrhenius, Brønsted-Lowry, and a Lewis acid-base reaction because it involves protons, electrons and hydroxide ions.
III. N2 + 3 H2 ---> 2NH3 is a Lewis acid-base reaction because it involves sharing of electrons only.
IV. CN− + H2O ---> HCN + OH is both a Lewis and Brønsted-Lowry acid-base reaction because both protons and electrons sharing is involved.
In a Bronsted-Lowry acid-base reaction reaction, an acid donates protons which is accepted by the base.
The following are useful definitions of acids and bases;
An Arrhenius acid produces hydrogen ion as its only positive ion in solution while an Arrhenius base produces hydroxide ion as its only negative ion in solution.A Bronsted-Lowry acid donates hydrogen ions while a Bronsted-Lowry base accepts hydrogen ionsA Lewis acid accepts lone pairs of electrons while a Lewis base donates lone pairs of electrons.Based on these, we can now classify the reactions accordingly;
Cu^2+ + 4Cl− ------>[CuCl4[^2− Lewis acid-base reaction Al(OH)3 + 3HNO3 -----> Al^3+ + 3H2O + 3NO3^− Arrhenius acid-base reactionN2 + 3H2 ----> 2NH3 NoneCN− + H2O ------> HCN + OH^- Bronsted-Lowry acid-base reactionLearn more: https://brainly.com/question/9352088
An EpiPen, used to treat anaphalactic allergic reactions, contains 0.30 mg of epinephrine. The concentration of epinephrine in each syringe is 1.0 mg/mL. What is the volume, in milliliters (mL), of solution in each syringe
Answer:
0.3mL
Explanation:
Mass = 0.30mg
Concentration = 1.0 mg/mL
Volume = x
The relationship between the three parameters is given as;
Concentration = Mass / Volume
Making Volume our subject of interest we have;
Volume = Mass / Concentration
Substituting the values we have;
Volume = 0.30 mg / 1 mg/mL = 0.3mL
How is excitation in spectroscopy brought about
Answer: the exciation of molecules is brount by absorption of energy in spectroscpy
Explanation:
A chemistry student is given of a clear aqueous solution at . He is told an unknown amount of a certain compound is dissolved in the solution. The student allows the solution to cool to . At that point, the student sees that a precipitate has formed. He pours off the remaining liquid solution, throws away the precipitates, and evaporates the water from the remaining liquid solution under vacuum. More precipitate forms. The student washes, dries and weighs the additional precipitate. It weighs 50,0 g.
Using only the information above, can you calculate the solubility of X in water at 16. C. If you said yes, calculate it.
Answer:
Solubility cannot be calculated.
Explanation:
To calculate the solubility of X it is necessary to know the value of the mass of the solute (X) that can be dissolved in 100 g of water.
[tex]Solubility = \frac{Solute mass}{100 grams of water}[/tex]
Taking into account that we do not know the value of the mass of the solution, therefore the value of the solubility of the compound cannot be determined.
A microwave has a wavelength of 0.028 m. What us this wavelength in scientific notation
Answer:
2.8 times 10^ -2
Explanation:
scientific notation is supposed to be a number between 1 and 10
the decimal point moves 2 to the right in order to get 2.8 which makes the exponent negative
11. Caproic acid, which is responsible for the foul odor of dirty socks, is composed of C, H, and O atoms. Combustion of a 0.225-g sample of this compound produces 0.512 g CO2 and 0.209 g H2O. (a) What is the empirical formula of caproic acid
Answer:
C3H6O
Explanation:
Step 1:
Data obtained from the question include the following:
Mass of the compound = 0.225g
Mass of CO2 = 0.512g
Mass of H2O = 0.209g
Step 2:
Determination of the masses of carbon, hydrogen and oxygen present in the compound.
This is illustrated below:
For Carbon, C:
Molar mass of CO2 = 12 + (2x16) = 44g/mol
Mass of C in CO2 = 12/44 x 0.512 = 0.1396g
For Hydrogen, H:
Molar mass of H2O = (2x1) + 16 = 18g/mol
Mass of H in H2O = 2/18 x 0.209 = 0.0232g
For Oxygen, O:
Mass of O = 0.225 – (0.1396 + 0.0232)
Mass of O = 0.0622g
Step 3:
Determination of the empirical formula for caprioc acid.
This can be obtain as follow:
C = 0.1396g
H = 0.0232g
O = 0.0622g
Divide by their molar mass
C = 0.1396/12 = 0.0116
H = 0.0232/1 = 0.0232
O = 0.0622/16 = 0.0039
Divide by the smallest
C = 0.0116/0.0039 = 3
H = 0.0232/0.0039 = 6
O = 0.0039/0.0039 = 1
Therefore, the empirical formula for caprioc acid is C3H6O
C3H7-C(=O)-NH2 IUPAC NAME ?
Answer:
Amide
Explanation:
O=NH2 is the Amide group versus NH2, which is the amine group.
Answer:
Butamide
Explanation:
C3H7-C(=O)-NH2 IUPAC NAME
C4H9NO
H H H
H - C - C - C - C = O
H H H N - H
H
But amide
Amide because R-CO-NH2 ie C(=O)-NH2
But because 4 Cabon
The temperature program for a separation starts at a temperature of 50 °C and ramps the temperature up to 270 °C at a rate of 10 °C/minute. Which statement is NOT true for this separation?
A) At 10 °C/minute, a total of 22 minutes is needed to reach 270 oC.
B) Strongly retained solutes will remain at the head of the column while the temperature is low.
C) Weakly retained solutes will separate and elute early in the separation.
D) The vapor pressure of strongly retained solutes will increase as temperature increases.
E) Strongly retained analytes will give broad peaks.
Answer:
The correct answer to the question is Option E (Strongly retained analytes will give broad peaks).
Explanation:
The other options are true because:
A. Initial temp = 50 °C
Final temp = 270 °C
Differences in temp = 270 - 50 = 220°C
Rate = 10 °C/minute.
So, at 10 °C/minute,
total of 220°C /10 °C = number of minutes required to reach the final temp.
220/10 = 22 minutes
B. A column has a minimum and maximum use temperature. Solutes that are already retained would remain stationary while temperatures are low. This would only change if there is an increase in temperature. Heat transfers more energy to the liquid which would make the solute interact with the column phase.
C. Weakly retained solutes may contain larger molecules, will separate by absorbing into the solvent early in separation making the mobile phase separates out into its components on the stationary phase.
D. Retained solute's vapor pressure is higher at higher temperatures making it possible for particle to escape more from the solute when the temperature is high than when it is low.
When 8.1 g of an unknown non-electrolyte is dissolved in 50.0 g of carbon tetrachloride, the boiling point increased by 3.67 degrees C. If the Kbp of the solvent is 4.95 K/m, calculate the molar mass of the unknown solute.
Answer:
218.3 g/mol
Explanation:
Boiling point elevation occurs when a solute is added to a solvent increasing the boiling point of the solution with regard to the pure solvent.
The law is:
ΔT = Kb×m×i
Where ΔT is change in temperature (3.67°C), Kb is the boiling point constant of the solvent (4.95°C/m), m is molality of the solution and i is Van't Hoff factor (1 for a non-electrolyte).
3.67°C = 4.95°C/m×m×i
0.7414m = molality of the solution (Moles solute / kg solvent).
As the mass of the solvent is 50.0g = 0.0500kg:
0.7414m = Moles solute / 0.0500kg
0.0371 = moles of solute
As the mass of the solute is 8.1g, molar mass of the solute (Ratio between mass in g and moles) is:
8.1g / 0.0371mol =
218.3 g/molWhat are plastic bottles made of?
Polyethylene
halogen
silicon
Alkyl groups
Answer:
polyethylenes
Explanation:
the plastic bottles used to hold potable water and other drinks are made from polyethylene because, the material is both strong and light.
hope this helped!
Answer: Polyethylenes
Explanation: I got 100% on the test :)
30
Drag each number to the correct location on the equation. Each number can be used more than once, but not all numbers will be used.
Balance the equation with the correct coefficients.
2
3
4
5
SIO2 +
HF → SiF4 +
H2O
Reset
Next
Answer:
The balanced equation is given below:
SiO2 + 4HF —> SiF4 + 2H2O
The coefficients are 1, 4, 1, 2
Explanation:
The equation for the reaction is given below:
SiO2 + HF —> SiF4 + H2O
The above equation can be balance by as follow:
There are 4 atoms of F on the right side and 1 atom on the left side. It can be balance by putting 4 in front of HF as shown below:
SiO2 + 4HF —> SiF4 + H2O
Therefore are 4 atoms of H on the left side and 2 atoms on the right side. It can be balance by putting 2 in front of H2O as shown below:
SiO2 + 4HF —> SiF4 + 2H2O
Now the equation is balanced.
A 1.44 L buffer solution consists of 0.137 M butanoic acid and 0.275 M sodium butanoate. Calculate the pH of the solution following the addition of 0.069 moles of NaOH . Assume that any contribution of the NaOH to the volume of the solution is negligible. The Ka of butanoic acid is 1.52×10−5 .
Answer:
The answer is "[tex]P^{H}=5.379[/tex]".
Explanation:
[tex]\ NaOH \ value = \frac{n}{v}\\\\[/tex]
[tex]=\frac{0.069\ moles}{0.144L}\\\\=0.04791\ M[/tex]
[tex]\ Ka=1.52 \times 10^{-5}\\\\P^{ka} = -10g \ ka \\\\[/tex]
[tex]= -10 \times 1.52 \times 10^{-5}\\\\= 4.82\\[/tex]
Equation:
[tex]CH_3CH_2CH2COOH+NaOH\rightarrow CH_3CH_2CH_2COONa +H_2O\\\\[/tex]
[tex]\boxed{\left\begin{array}{ccccc}I &0.137 &0.04791 &0.275 & -- \\ C &-0.04791 &-0.04791 &+0.04791 & -- \\E &0.08909 &0&0.32291 & -- \end{array}\right}[/tex]
[tex]P^{H}= P^{ka}+\log\frac{CH_3CH_2CH_2COONa}{CH_3CH_2CH_2COOH}\\\\[/tex]
[tex]= 4.82+\log\frac{0.32291}{0.08909}\\\\=5.379[/tex]
The decomposition of Ca(OH)2(s) intoCaO(s) and H2O(g) at constant pressure requires the addition of 109 kJ of heat per mole of Ca(OH)2.
A. Write a balanced thermochemical equation for the reaction.
B. Draw an enthalpy diagram for the reaction, showing the activation energy, Ea, and the enthalpy change for the reaction.
Answer:
A. Ca(OH)2 ----> CaO + H2O; ∆H = +109KJ
B. Check attached document below for the enthalpy diagram
Explanation:
A thermochemical equation is a balanced chemical equation in which enthalpy change is variable. It tells about the nature of the reaction.
Enthalpy change is the difference between the heat content of the products and reactants in a thermochemical equation.
∆H is negative for an exothermic reaction (a reaction where heat is given out), while it is positive for an endothermic reaction ( a reaction in which heat is added).
The activation energy, Ea, is the minimum amount of energy reactant particles must possess in order for a reaction to proceed towards product formation.
As per the decomposition of the Ca(OH) 2 and the CaO the constant pressure needs to be added of the 109KJ.
The balance thermochemical equation for the reaction is expressed as Ca(OH)2 ----> Ca O + H2O; ∆H = +109KJThe diagram for the reaction and the activation energy is given above.Learn more about decomposition.
brainly.com/question/14797703.
What happens at this point
Answer:
What are you referring to exactly
Explanation:
Answer: C
Explanation:
There is a difference in air pressure. That's what I put and I got a 92.
g The solution you created in this simulation was a 0.300M NH4Cl solution. The lab also stated that, in g/L, this concentration was 16.0 g/L. Show the calculations that prove that to be true.
Answer:
16.0473 g/L
Explanation:
0.300 M=
0.300 mol/L x 53.491 grams/mol = 16.0473 grams/L
The concentration of the 0.300M NH₄Cl solution in g/L will be equal to 16.04 g/L.
What is the molarity?The concentration of the solution can be determined if we have the molecular formula of the compound and its molecular weight. We can easily determine the majority of a solution from the moles of solute and the volume of the solution.
The molarity of a solution can be evaluated from the number of moles of a solute per liter of a solution.
The Molarity can be determined from the formula mentioned below:
Molarity (M) = Moles of solute (n)/Solution's volume ( in L)
Given, the molarity of NH₄Cl solution = 0.300 M
We can also write it as 0.300 mol/L
It means 0.300 moles in one liter.
The molar mass of NH₄Cl = 53.5 g/mol
Then the mass of 0.300 mol of NH₄Cl = 0.300 ×53.5 = 16.04 g
Therefore, the concentration of NH₄Cl solution is 16.04g/L is equivalent to 0.300 M.
Learn more about molarity, here:
brainly.com/question/8732513
#SPJ5
Calculate the standard entropy of reaction at 298 K for the reaction Hg(liq) + Cl2(g) → HgCl2(s) The standard molar entropies of the species at that temperature are: Sºm (Hg,liq) = 76.02 J / (K mol) ; Sºm (Cl2,g) = 223.07 J / (K mol) ; Sºm (HgCl2,s) = 146.0 J / (K mol)
Answer:
−153.1 J / (K mol)
Explanation:
Calculate the standard entropy of reaction at 298 K for the reaction Hg(liq) + Cl2(g) → HgCl2(s) The standard molar entropies of the species at that temperature are: Sºm (Hg,liq) = 76.02 J / (K mol) ; Sºm (Cl2,g) = 223.07 J / (K mol) ; Sºm (HgCl2,s) = 146.0 J / (K mol)
Hg(liq) + Cl2(g) → HgCl2(s)
Given that;
The standard molar entropies of the species at that temperature are:
Sºm (Hg,liq) = 76.02 J / (K mol) ;
Sºm (Cl2,g) = 223.07 J / (K mol) ;
Sºm (HgCl2,s) = 146.0 J / (K mol)
The standard molar entropies of reaction = Sºm[products] - Sºm [ reactants]
= 146.0 J / (K mol) – [76.02 J / (K mol) +223.07 J / (K mol) ]
= -153.09 J / (K mol)
= or -153.1 J / (K mol)
Hence the answer is −153.1 J / (K mol)
Trans-4-hexen-3-ol can be synthesized starting from acetaldehyde. One of the key reagents is ethyl grignard.
1. Synthesize ethyl grignard from acetaldehyde in the steps below using the reagents provided.
2. Synthesize (trans)-4-hexen-3-ol from acetaldehyde.
find the given attachment
carbon dioxide is a non-polar molecule true or false
Answer:
True
Explanation:
Due to the arrangement of the molecule, a carbon dioxide molecule is non-polar.
The acetate ion is the conjugate base of the weak acid acetic acid. The value of Kb for CH3COO-, is 5.56×10-10. Write the equation for the reaction that goes with this equilibrium constant.
Answer: The equation for the reaction that goes with this equilibrium constant is [tex]5.56\times 10^{-10}=\frac{[CH_3COOH]}{[CH_3COO^-]\times [H^+]}[/tex]
Explanation:
[tex]CH_3COOH\rightarrow CH_3COO^-+H^+[/tex]
Here [tex]CH_3COOH[/tex] donates a proton and thus behaves as an acid and forms [tex]CH_3COO^-[/tex] which is called as the conjugate base of [tex]CH_3COOH[/tex]
The dissociation constant of acids is given by the term [tex]K_a[/tex] and the dissociation constant of bases is given by the term [tex]K_b[/tex] and is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios.
[tex]K_a[/tex] for [tex]CH_3COOH[/tex] :
[tex]K_a=\frac{[CH_3COO^-]\times [H^+]}{[CH_3COOH]}[/tex]
[tex]CH_3COO^-+H^+\rightarrow CH_3COOH[/tex]
[tex]K_b=\frac{[CH_3COOH]}{[CH_3COO^-]\times [H^+]}[/tex]
[tex]5.56\times 10^{-10}=\frac{[CH_3COOH]}{[CH_3COO^-]\times [H^+]}[/tex]
The equation for the reaction that goes with this equilibrium constant is [tex]K_b=\frac{[CH_3COOH]}{[CH_3COO^-]\times [H^+]}[/tex]
What is the reactant(s) in the chemical equation below?
2Al(s) + 2NaOH(aq) + 2H2O()
2NaAlO2(aq) + 3H2(9)
A. 2Al(s) + 2NaOH(aq) + 2H200)
B. 2NaAlo2(aq) + 3H2(g)
C. 2Al(s)
D. 3H2(g)
Answer:
A
Explanation:
They are all found in the reactants side
Which process is a physical change
Answer:
a physical change is something that has not been modified chemically and can possibly be changed back to the state it was once before. A physical change keeps all the same atoms and none of them is modified.
Example:
When a block of clay is morphed into a giraffe statue, it can be morphed back to its original state. If someone burnt the block of clay, the atoms would be modified and it would be unable to go back to its previous state.
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(If you're referring to a question with these answers)
A. iron rusting
B. milk turning to curd
C. water boiling
D. paper burning
E. hard water staining pipes
-----------------------------------------------------------------------------------------------------------------
Answer:
C. Water Boiling
(If you are referring to a question with these answers I think this is the correct answer if not I do apologize)
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Aspirin is usually packaged with
A. acetic anhydride
B. salicylic acid
C. buffering agents
Answer:
Aspirin is usually packaged with C. buffering agents.
Explanation:
Enter your answer in the provided box. A sample of an unknown gas effuses in 14.5 min. An equal volume of H2 in the same apparatus under the same conditions effuses in 2.42 min. What is the molar mass of the unknown gas
Answer:
Molar mass = 71.76 g/mol
Explanation:
The relationship between molar mass and rate of effusion is given as;
Vh / Vu = √ (Mu / Mh)
The rate of effusion of a gas is inversely proportional to the square root of the mass of its particles.
Rate = volume / time (Assuming Volume = 1)
Vh = Rate of effusion of Hydrogen = 1 / 2.42
Vu = Rate of effusion of unknown gas = 1 / 14.5
Mh = Molar mass of hydrogen = 2
Mu = Molar mass of unknown gas = x
Substituting into the formular, we have;
(1 / 2.42) / (1 / 14.5) = √ ( x / 2)
5.99 = √ ( x / 2)
35.88 = x / 2
x = 71.76
