Answer:
a) Can be cut into tiny pieces - Physical Change
b) Fizzling occurs when placed water -Chemical Change
c) Light is emitted when burned -Chemical Change
d) Turns to ash -Chemical Change
Explanation:
In Chapter 4, we will learn that single bonds experience free rotation at room temperature, while double bonds do not. Consider the two C-N bonds in the structure. One of these bonds exhibits free rotation, as expected for a single bond, but the other C-N bond exhibits restricted rotation. Identify the C-N bond with restricted rotation, and justify your answer by drawing resonance structures.
Answer:
Explanation:
The main objective here is to draw a diagram of an heterocyclic compound containing two C-N bonds in the structure. One with free rotation, as expected for a single bond, but the other C-N bond exhibits restricted rotation. After that ; we will identify the C-N bond with restricted rotation, and also justify our answer by drawing resonance structures.
So; the first image below shows the structure of the heterocyclic compound containing two C-N bonds in the structure with One with free rotation, as expected for a single bond, but the other C-N bond exhibits restricted rotation. From the first diagram. the squared area indicates the C-N bond that exhibits restricted rotation.
The amide bonds in the C-N bonds offers the resonance characteristics and thus exhibits restricted rotation. The resonance is shown in the second image below
A gas occupies a volume of 180 mL at 35 °C and 95.9 kPa. What is the volume of the gas at conditions of STP?
Answer:
the volume of the gas at conditions of STP = 151.04998 ml
Explanation:
Data given:
V1 = 180 ml
T1 = 35°C or 273.15 + 35 = 308.15 K
P1 = 95.9 KPa
V2 =?
We know that at STP
P2 = 1 atm or 101.3 KPa
T2 = 273.15 K
At STP the pressure is 1 atm and the temperature is 273.15 K
applying Gas Law:
[tex]\frac{P_1V_1}{T_1} =\frac{P_2V_2}{T_2}[/tex]
putting the values in the equation of Gas Law:
[tex]V_2=\frac{P_1V_1T_2}{T_1P_2}[/tex]
V_2 =[tex]\frac{95.9\times180\times273.15}{308.15\times101.3}[/tex]
V2 = 151.04998
therefore, V2 = 151.04998 ml
Answer:
151 mL is the correct answer to the given question .
Explanation:
We know that
[tex]PV =n RT[/tex]
Where P =pressure ,V=volume and T=Temperature
Given
P=95.9 kPa.
V=[tex]180 * 10 ^{-3}[/tex]
R=25/3
T=273 + 35 =308k
Putting these value into the equation we get
[tex]95.9\ * 180\ *\ 10^{-3} \ =\ n * \frac{25}{3} * 308[/tex]
n=[tex]6.72 * 10^{-3}[/tex]
Now using the equation
[tex]n= \ \frac{V}{22.4}[/tex]
[tex]6.72 * 10^{-3} =\frac{V}{22.4}\\ V\ =\ 150.6mL[/tex]
This can be written as 151mL
when a car drives down a street, what evergy conversions are happening?
In general,for a gas at a constant volume?
Answer:
The pressure of a gas is directly proportional to its Kelvin temperature if the volume is kept constant. At constant volume and temperature, the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the component gases.
Explanation:
What mass of salt would you need to add to 1.00kg of water to achieve a freezing point of -5 degrees C
Answer:
The type of salt to be added to the water is not known from the question but no worries, I will try to give you the step by step procedure to answer any type of question similar to this.
To answer this question, we should know some facts.
1. the molar freezing point depression constant of water (Kf) = 1.86 K kg/mol
2. the molar mass of the salt if NaCl = 58.5 g/mol ; KCl = 74.5 g/mol
3. since the salt can dissociate if NaCl or KCl into two ions, the Van't Hoff factor ( i )= 2
Note that: the change in freezing point, molarity, deepression constant and van't Hoff factor are related by this formula;
ΔTf = i Kf m
So lets take NaCl as the salt:
Molar mass = 58.5 g/mol
Van't Hoff factor = 2
1. calculate the number of moles
So we can calculate the molarity of the salt NaCl from the formula;
m = ΔTf / i Kf
m = 5 / 2 * 1.86
m = 5 / 3.72
m = 1.344 mol/kg
2. calculate the number of moles of the salt required
Next is to multiply the molarity by the mass of water. Density of water = 1kg/L
number of moles = 1.344 mol/kg * 1 Kg/L * 1 kg water
number of moles = 1.344 moles.
3. calculate the mass of the salt.
numner of moles = mass / molar mass
mass = number of moles * molar mass
mass = 1.344 * 58.5
mass = 78.624 g of NaCl salt.
You can follow these steps to solve for the type of salt you are given in the question.
Consider the following reaction where Kc = 2.90×10-2 at 1150 K: 2 SO3 (g) 2 SO2 (g) + O2 (g) A reaction mixture was found to contain 4.71×10-2 moles of SO3 (g), 5.00×10-2 moles of SO2 (g), and 4.53×10-2 moles of O2 (g), in a 1.00 liter container.
Answer:
The reaction is not in equilibrium and must move in a backward manner i.e towards the reactant so that it will attain equilibrium
Explanation:
The complete question is as follows;
Consider the following reaction where Kc = 2.90×10-2 at 1150 K: 2 SO3 (g) 2 SO2 (g) + O2 (g) A reaction mixture was found to contain 4.71×10-2 moles of SO3 (g), 5.00×10-2 moles of SO2 (g), and 4.53×10-2 moles of O2 (g), in a 1.00 liter container.
Is the reaction at equilibrium? If not, what direction must it run in order to reach equilibrium? The reaction quotient, Qc, equals . The reaction A. must run in the forward direction to reach equilibrium. B. must run in the reverse direction to reach equilibrium. C. is at equilibrium.
Solution
The first thing to do here is to calculate the pressure of each of the gases. This would be useful in the equilibrium calculations. We calculate this by dividing the respective number of moles by the volume of the container.
Now, since the volume of the container is 1L, then the number of moles will be equal to the pressure of the gaseous substances, although units will be different.
So, [SO3] = 4.71 * 10^-2 mol/L
[SO2] = 5.00 * 10^-2 mol/L
[O2] = 4.53 * 10^-2 mol/L
The equation of the reaction is as follows;
[tex]2SO_{3(g)}[/tex] ⇆ [tex]2SO_{2(g)}[/tex] + [tex]O_{2(g)}[/tex]
We proceed to calculate the reaction quotient Qc
Mathematically Qc for this reaction = [[tex]SO_{2}[/tex]]^2 × [[tex]O_{2}[/tex]]/ [[tex]SO_{3}[/tex]]^2
Qc = {(5 * 10^-2)^2 * (4.53 * 10^-2)}/ (4.71 * 10^-2)^2 = 5.11 × 10^-2 mol/L
Now, we are given that the value of Kc = 2.9 * 10^-2 which is less than Qc
Since Kc < Qc, the backward reaction is favored.
Now to the question;
The reaction is not in equilibrium and must move in a backward manner i.e towards the reactant so that it will attain equilibrium
3. Are all amino acids are chiral? Why or why not? Protein only contain ____ (L-/D-) amino acids. Which organic molecule is the standard molecule for L-/D- configuration system? The chiral carbon in L-Alanine is ______ (R- /S-) configuration, but in D-Alanine is ________ (R-/S-) configuration.
Answer:
Protein are essential in body cells for the repair of worn out tissues. Amino acid is gotten when protein is broken down under certain conditions.
All amino acids are chiral with the exception of glycine. This means they have a central carbon atom with the R-, -COOH, and -NH2 group attached to it.
Protein contain only L amino acid because the L amino acid is the only type used by cells.
The chiral carbon in L-Alanine is S-configuration and D-Alanine is R-configuration.
Hcl and 1-isopropylcyclohexane formation
Answer:
Spahgetti
Explanation:
dropping an Alka-Seltzer tablet into a glass of water _________________________________________ b. bleaching a stain _________________________________________ c. burning a match _________________________________________ d. rusting of an iron nail
Answer:
Hi there!
When dropping Alka-Seltzer into a glass of water, bubbles immediately appear and the solid substance “disappears”, dissolves, into the water. This forms a new compound, a liquid, which means a reaction took place.
At the end of a reaction it is important to remove the solvent from a solid product (more than one answer may be correct):
a. So that the melting point can be determined.
b. So that clean NMR spectra can be obtained that do not contain solvent peaks.
c. So that the yield can be determined.
d. So that the solvent can be reused.
Answer:
(B.) and (C.)
b. So that clean NMR spectra can be obtained that do not contain solvent peaks.
c. So that the yield can be determined.
Explanation:
The solvent used in Nuclear Magnetic Resonance (NMR) spectrometer is Trimethyl silane (TMS), a neutral solvent which doesn't give off any signals. Other solvents could have interactions with the radiation, and disrupt the spectra.
Furthermore, for accurate determination of the actual yield and overall percentage yield, solid must be separated from the solvent, dried and weighed.
I hope this was explanatory enough.
Describe why some acids are strong while other acids are weak
Answer:
I hope this help you. Mark me as brainliest and rate pleaseExplanation:
the terms strong and weak as applied to acids. As a part of this it defines and explains what is meant by pH, Ka and pKa.
It is important that you don't confuse the words strong and weak with the terms concentrated and dilute.
As you will see below, the strength of an acid is related to the proportion of it which has reacted with water to produce ions. The concentration tells you about how much of the original acid is dissolved in the solution.
It is perfectly possible to have a concentrated solution of a weak acid, or a dilute solution of a strong acid.
Match the following aqueous solutions with the appropriate letter from the column on the right. 1. 0.13 m FeCl3 A. Highest boiling point 2. 0.19 m Mg(CH3COO)2 B. Second highest boiling point 3. 0.30 m KI C. Third highest boiling point 4. 0.53 m Glucose(nonelectrolyte) D. Lowest boiling point An error has been detected in your answer. Check for typos,
Answer:0.30 m KI ---- A. Highest boiling point
0.19 m Mg(CH3COO)2 ---- B. Second highest boiling point
0.53 m Glucose(nonelectrolyte) ---- Third highest boiling point-C
0.13 m FeCl3---- Lowest boiling point-D
Explanation:
Using the boilng point elevation formula
ΔTb=m* kb *i
where m= molality
kb= elevated boiling point constant( here kb values will be same for all soluton)
i= vant hoff factor = number of ions present in a solution
Using the number of ions and molarity present in a solution as a collagative property, since kb is constant, we can determine which of the species has the highest boiling point.
1.) 0.13 m FeCl3= Fe³⁻ + Cl⁻
i=4
ΔTb=m* kb* i= molarity x number of ionsx Kb= 0.13 x 4= 0.52kb
2) 0.19 m Mg(CH3COO)2 = Mg²⁺ + CH₃COO⁻
i= 3
ΔTb=m* kb* i= molarity x number of ions= 0.19 x 3= 0.57kb
3. 0.30 m KI = K⁺ + I⁻
i= 2
ΔTb=m *kb *= imolarity x number of ions xKb= 0.30x 2= 0.60kb
4. 0.53 m Glucose(nonelectrolyte) =
i= 1 for nonelectroytes
ΔTb=m* kb* i = molarity x number of ionsx Kb= 0.53 x 1= 0.53Kb
therefore,
0.30 m KI ---- A. Highest boiling point
0.19 m Mg(CH3COO)2 ---- B. Second highest boiling point
0.53 m Glucose(nonelectrolyte) ---- Third highest boiling point
0.13 m FeCl3---- Lowest boiling point
Which statement BEST describes how a golf club does "work" on a golf ball?
(A) When the club hits the ball the club transfers all of its kinetic energy to the ball.
(B) All of the kinetic energy from the club is transferred to the ball as they both move through the air.
(C)
Some of the kinetic energy from the golf club is transferred to the ball and some transforms into sound
and heat, but the total energy remains the same.
(D) The golf club loses kinetic energy when it hits the ball and the ball gains kinetic energy from the air as it
travels
Answer:
C
Explanation:
It looks pretty reasonable to me
What is the Arrhenius definition of an acid? A substance that increases H3O+ concentration when it is dissolved in water. A substance that increases OH– concentration when it is dissolved in water. A compound that donates protons. A compound that accepts protons.
Answer:
A substance that increases H3O+ concentration when it is dissolved in water.
Explanation:
Note that H3O+ and H+ are used quite interchangeably in chemistry.
An acid makes the H+ content higher, thereby decreasing the pH.
Answer:
a
A substance that increases H3O+ concentration when it is dissolved in water.
Explanation:
Is chemical engineering suits for a person who gets bored fast and needed to learn new things?
Answer:
yes
Explanation:
because it will keep them entertained and will learn new things
Two hypothetical ionic compounds are discovered with the chemical formulas XCl2 and YCl2, where X and Y represent symbols of the imaginary elements. Chemical analysis of the two compounds reveals that 0.25 mol XCl2 has a mass of 100.0 g and 0.50 mol YCl2 has a mass of 125.0 g. (a) What are the molar masses of XCl2 and YCl2
Answer:
THE MOLAR MASS OF XCL2 IS 400 g/mol
THE MOLAR MASS OF YCL2 IS 250 g/mol.
Explanation:
We calculate the molar mass of XCL2 and YCL2 by bringing to mind the formula for molar mass when mass and amount or number of moles of the substance is given.
Number of moles = mass / molar mass
Molar mass = mass / number of moles.
For XCL2,
mass = 100 g
number of mole = 0.25 mol
So therefore, molar mass = mass / number of moles
Molar mass = 100 g / 0.25 mol
Molar mass = 400 g/mol.
For YCL2,
mass = 125 g
number of mole = 0.50 mol
Molar mass = 125 g / 0.50 mol
Molar mass = 250 g/mol.
So therefore, the molar mass of XCL2 and YCL2 IS 400 g/mol and 250 g/mol respectively.
Which correctly lists the three processes that are affected by freeze and thaw cycles?
creep, landslide, and deposition
deposition, creep, and weathering
landslide, slump, and deposition
O slump. weathering, and creep
Answer:
slump. weathering, and creep
Explanation:
Freezing and thawing cycle in geology is the process in which water gets in between soil space or rock cracks, freeze in a cold season, and then melt in a warmer season, exerting a force on the soil or rock around it. This force is due to the expansion and contraction of water when it changes from ice to liquid water.
The three geological processes slump, weathering and creep all depend on thawing and freezing cycle among other factors.
Slump: Slump is a type of geological process that occurs when coherent mass of loosely consolidated materials or a rock layer moves a short distance down a slope. The movement of a slump is characterized by sliding along a concave-upward or planar surface. Causes includes earthquake shocks, thorough wetting, freezing and thawing, undercutting, and loading of a slope.Weathering: This is a geological process that results in the gradual disintegration of rocks into smaller sizes. It is one of the most important soil formation process, and is different from erosion by the degree of movement of the soil formed. Weathering does not move the soil from its origin. Thawing and freezing cycle plays a major role in weathering by helping crack up the rocks and by also tearing the rock apart. plays a major role.Creep: This is the slow, often imperceptible downslope movement of soil or other debris. The effects of creep is often seen in the presence of physical characteristics like bent trees, tilted fences, and cracked walls. Creep is caused by multiple factors, of which heaving is likely the most important process. Heaving involves the expansion and contraction of rock fragments, and occurs during cycles of wetting and drying, as well as freezing and thawing.Answer:
It is slump, weathering and creep
Explanation:
Took the test on edg
Wax melts when it is heated which most likely describes what is true of the result of this reaction
Answer:
Was is a hydrocarbon therefore when heated some co2 escapes but later solidifies
Explanation:
Hope it helps
Which of the following obervations would be classified as a physical change? A) Fireworks releasing light B) Antacid fizzing in water C) Steam condensing on a mirror D) Apple turning brown
Answer:
C) Steam condensing on a mirror
Explanation:
This was just a change in the physical state.
What is the rate of a reaction if the value of kis 0.1, [A] is 1 M, and [B] is 2 M?
Rate = K[A]2[B]2
A. 1.6 (mol/L)/s
B. 0.8 (mol/L)/S
C. 0.2 (mol/L)/S
D. 0.4 (mol/L)/S
Answer:
D. 0.4 (mol/L)/S
Explanation:
You simply have to plug in the given values into the rate law.
Rate = k[A][B]
Rate = (0.1)(1)²(2)²
Rate = (0.1)(1)²(4)²
Rate = 0.4
Constructive interference occurs when the compression of one wave meets
up with the compression of a second wave.
A. True
B. False
Answer:
True
Explanation:
Given a K value of 0.43 for the following aqueous equilibrium, suppose sample Z is placed into water such that it’s original concentration is 0.033 M. Assume there was zero initial concentration of either A(aq) or B(aq). Once equilibrium has occurred, what will be the equilibrium concentration of Z?
2A(aq) + B(aq) <> 2Z (aq)
Answer:
[Z] = 0.00248M
Explanation:
Based in the reaction:
2A(aq) + B(aq) ⇄ 2Z (aq)
K of the reaction is defined as:
K = [Z]² / [A]²[B] = 0.43
If you add, in the first, just 0.033M of Z, concentrations in equilibrium are:
[Z] = 0.033M - 2X
[A] = 2X
[B] = X
Replacing in K equation:
0.43 = [0.033M - 2X]² / [2X]² [X]
0.43 = [0.033M - 2X]² / [2X]² [X]
0.43 = 4X² -0.132X + 0.001089 / 4X³
1.72X³ - 4X² + 0.132X - 0.001089 = 0
Solving for X:
X = 0.01526M
Replacing, concentration in equilibrium of Z is:
[Z] = 0.033M - 2*0.01526M = 0.00248M
Answer:
Less than 0.033 M
Explanation:
Hello,
In this case, given the equilibrium:
[tex]2A(aq) + B(aq) \rightleftharpoons 2Z (aq)[/tex]
Thus, the law of mass action is:
[tex]K=\frac{[Z]^2}{[A]^2[B]}[/tex]
Nevertheless, given the initial concentration of Z that is 0.033 M, we should invert the equilibrium since the reaction will move leftwards:
[tex]\frac{1}{K} =\frac{[A]^2[B]}{[Z]^2}=2.33[/tex]
Know, by introducing the change due to the reaction extent, we can write:
[tex]2.33=\frac{(2x)^2*x}{(0.033M-2x)^2}[/tex]
Which has the following solution:
[tex]x_1=2.29M\\x_2=0.0181M\\x_3= 0.0153M[/tex]
But the correct solution is [tex]x=0.0153M[/tex] since the other solutions make the equilibrium concentration of Z negative which is not possible. In such a way, its concentration at equilibrium is:
[tex][Z]_{eq}=0.033M-2*0.0153M=0.0024M[/tex]
Which is of course less than 0.033 M since the addition of a product shift the reaction leftwards in order to reestablish equilibrium (Le Chatelier's principle).
Regards.
The metalloid that has three valence electrons is .
Answer:
Boron
Explanation:
Answer: a. boron
Explanation: bc the Boron Family is named after the first element in the family. atoms in this family have 3 valence electrons. this family includes a metalloid (boron), and the rest are metals.
A sample of thallium(III) peroxide, Tl2(O2)3, contains 2.45 mol of thallium(III) ions. The number of moles of peroxide ions in the sample is
Answer:
The correct answer is 3.675 moles.
Explanation:
Based on the question, the reaction taking place is,
Tl₂(O₂)₃ ⇒ 2Tl⁺³ + 3O₂⁻²
Thus, 1 mole of thallium peroxide comprise 2 moles of thallium and 3 moles of peroxide ions.
However, based on the given question, a sample of thallium peroxide comprise 2.45 moles of thallium ions. The moles of peroxide ions present in the sample will be,
= 2.45 × 3 / 2
= 3.675 moles.
Hence, the moles of peroxide ions present in the given sample is 3.675.
The reaction of hydrogen and iodine to produce hydrogen iodide has a Kc of 54.3 at 703 K. Given the initial concentrations of H2 and I2 are 0.453 M, what will the concentration of HI be at equilibrium
Answer:
[HI] = 0.7126 M
Explanation:
Step 1: Data given
Kc = 54.3
Temperature = 703 K
Initial concentration of H2 and I2 = 0.453 M
Step 2: the balanced equation
H2 + I2 ⇆ 2HI
Step 3: The initial concentration
[H2] = 0.453 M
[I2] = 0.453 M
[HI] = 0 M
Step 4: The concentration at equilibrium
[H2] = 0.453 - X
[I2] = 0.453 - X
[HI] = 2X
Step 5: Calculate Kc
Kc = [Hi]² / [H2][I2]
54.3 = 4x² / (0.453 - X(0.453-X)
X = 0.3563
[H2] = 0.453 - 0.3563 = 0.0967 M
[I2] = 0.453 - 0.3563 = 0.0967 M
[HI] = 2X = 2*0.3563 = 0.7126 M
tertbutylamine and ammonia. Which is more basic
Answer:
ammonia
Explanation:
At 25 °C, what is the hydroxide ion concentration, [OH−] , in an aqueous solution with a hydrogen ion concentration of [H+]=1.9×10−9 M?
Answer:
The correct answer will be "5.26 × 10⁻⁶".
Explanation:
The given values is:
[tex][H^{+}]=1.9\times 10^{-9} M[/tex]
As we know,
⇒ [tex]pH+pOH=14[/tex]
On taking log, we get
⇒ [tex]-log[H^{+}] + -log[OH^{-}] = 14[/tex]
Now,
Taking "log" as common, we get
⇒ [tex]log[H^{+}][OH^{-}]= -14[/tex]
⇒ [tex][H^{+}][OH^{-}]= 10^{-14}[/tex]
⇒ [tex][OH^{-}]=\frac{10^{-14}}{[H^{+}]}[/tex]
On putting the estimated value of "[tex][H^{+}][/tex]", we get
⇒ [tex]=\frac{10^{-14}}{1.9\times 10^{-9}}[/tex]
⇒ [tex]=5.26\times 10^{-6}[/tex]
Which of the following are not created by an arrangement of electric charges
or a current (the flow of electric charges)?
A. An electric field
B. A magnetic field
C. A quantum field
D. A gravitational field
Answer:
gravitational and quantum ARE NOT, but electric and magnetic ARE. there is a similar question to this but it's the exact opposite, so don't get confused
A student sets up the following equation to solve a problem in solution stoichiometry. (The ? stands for a number the student is going to calculate.) Enter the units of the student's answer
(1.26mol)1mL10^−3L / (7.9mol/L)= ?
Answer:
mL * L²
Explanation:
The question in t his problem is to calculate the units of the final answer.
The units in the numerator is mol, ml and L.
The unit in the denominator is mol/L
This leads us to;
Numerator / Denominator = mol * mL * L / (mol / L )
The final units is mL * L²
A 950.0 mL solution of potassium permanganate was made by dissolving 45.0 g KMnO4 in 750.0 mL of water. Assume water has a density of 1.00 g/mL. (Molar Mass for H = 1 , O = 16 , K= 39 , Mn= 55 ) The mole fraction of the solute =
Answer:
The correct answer is 6.67×10⁻³.
Explanation:
Based on the given question, the amount of solute (KmNO4) is 45 grams. The molecular weight of KmNO4 is 158 gram per mole. The moles of solute can be determined by using the formula,
n = mass/molecular weight
n = 45/158 = 0.28
The amount of solvent (water) given is 750 milliliters, and the density of water is 1 gm. per ml, 18 gram per mole is the molecular weight of water. So, the moles of solvent will be,
n = 750/18 = 41.7
The formula for calculating mole fraction is,
Mole fraction = mole of solute / (mass of solute + mole of solvent)
The mole fraction of solute can be determined by putting the values in the above mentioned formula,
Mole fraction of KmNO4 = 0.28/(0.28+41.7)
= 0.28/41.98
= 6.67 × 10⁻³ or 7 × 10⁻³.
