WorksheetsKr
Total questions: 50
Worksheet time: 3hrs 30mins
How can the particles of a solid be arranged?
In a uniform, crystalline structure, with limited motion
In an irregular, malleable manner, with limited motion
In close contact with each other, with continuous motion
Both a) and b)
At room temperature, substance A is a gas, whereas substance B is a solid. Substance A
Has stronger IMF than substance B
Has weaker IMF than substance B
Has IMF of the same degree of strength as substance B
The relative strength of the IMF cannot be determined without further information
How many moles of Oxygen gas are present at a volume of 10 L at 1 atm and 25 degrees Celsius? (MW Oxygen gas = 32 g/mol)
14 mol
0.41 mol
0.041 mol
4 mol
How many moles of carbon dioxide occupy a space of 16 liters at a pressure of 760 torr and a temperature of 250K? R=0.0821 Lat/ mmolK
22.4 mol
16.0 mol
6.02 mol
0.78 mol
A 2 mol sample of an ideal gas with a volume of 3L and temperature of 298K experiences a decrease in pressure of 4 atm. If the mass and temperature remain constant, what is the final volume?
3.74 L
3.97 L
2.56 L
2.11 L
A sample of chlorine gas fills a vessel at a temperature of 37 degree celsius. The vessel has a volume of 3L and experiences a pressure of 3atm. What is the mass of the chlorine gas in the vessel?
R=0.08206L∗atm/mol∗K
210.2 g
105.1 g
25.1 g
12.5 g
A sample of ideal gas is heated in a 2L vessel at a temperature of 320 Kelvin. The pressure in the vessel is 2.5 atm. What is the new pressure in the vessel if the volume is halved and the temperature is reduced to 250 Kelvin?
6.4 atm
3.9 atm
5.0 atm
0.98 atm
C12H22O11(aq)+H2O(l)→2C6H12O6(aq)
The chemical equation shown above represents the hydrolysis of sucrose. Under certain conditions, the rate is directly proportional to the concentration of sucrose. Which statement supports how a change in conditions can increase the rate of this reaction?
Increasing the amount of water in which the sugar is dissolved will increase the frequency of collisions between the sucrose molecules and the water molecules resulting in an increase in the rate of hydrolysis.
Increasing the concentration of sucrose will increase the rate of hydrolysis by increasing the frequency of the collisions between the sucrose and the water molecules.
Decreasing the temperature will increase the frequency of the collisions between the sucrose molecules and the water molecules resulting in an increase in the rate of hydrolysis.
Decreasing the concentration of sucrose will increase the rate of hydrolysis by increasing the frequency of the collisions between the sucrose and the water molecules
As a forward reaction continues in a “forward direction”, the reaction rate ___.
Increases because there are more available reactant particles to collide
Stays the same
Decreases because there are less reactants particles to collide
Decreases because there are more reactant particles to collide
Experimental data have shown that the rate law for the reaction: 2 HgCl2(aq) + C2O42-(aq) → 2 Cl-(aq) + 2 CO2 (g) + Hg2Cl2 (s) is: Rate = k[HgCl2][C2O42-]2
How will the rate of reaction change if the concentration of C2O42- is tripled and the concentration of HgCl2 is doubled?
Rate will increase by factor of 18
Rate will increase by factor of 9
Rate will decrease by factor of 18
Rate will decrease by factor of 9
Consider the following reaction: 2N2O(g)→ 2N2(g) + O2(g). Express the rate of the reaction in terms of the change in concentration of each of the reactants and products.
Rate=−21 ΔtΔ[N2O]=21 ΔtΔ[N2]=ΔtΔ[O2]
Rate=−ΔtΔ[N2O]=21 ΔtΔ[N2]=ΔtΔ[O2]
Rate=2 ΔtΔ[N2O]=2 ΔtΔ[N2]=ΔtΔ[O2]
Rate=−21 ΔtΔ[N2O]=2 ΔtΔ[N2]=ΔtΔ[O2]
Which of the following is LEAST effective in increasing the rate of reaction?
Increasing the pressure by adding an inert gas
Grinding a solid reactant into small particles
Increasing the temperature
Eliminating reverse reactions
The reaction rate of CO and NO2 in the reaction CO(g) + NO2(g) → CO2(g) + NO(g) is measured using the initial rates method. The results are tabulated below.
[CO] (M): 8x10-4, 8x10-4, 1.6x10-3
[NO2] (M) : 5.5x10-4, 1.1x10-3, 5.5x10-4
-[CO]/𝚫t (M/s): 8.4x10-8, 1.68x10-7, 1.68x10-7
The rate law is:
rate = 0.191[CO] [NO2]
rate = 0.191[CO][NO2]2
rate = [CO][NO2]
rate = 0.191 [CO]2[NO2]
CH3I+NaOH --> CH3OH+NaI
The rate of the reaction represented by the chemical equation shown above is rate=k [CH3I][NaOH]. Based on this information, which of the following claims is correct?
The rate of the reaction will double when the concentrations of both CH3I & NaOH are doubled.
The reaction will proceed at a slower rate with increasing temperature.
A larger amount of CH3OH will be produced if the concentrations of CH3I and NaOH are halved.
The rate of the reaction will double if the concentration of CH3I is doubled while keeping the concentration of NaOH constant.
Consider the following data showing the initial rate of a reaction (A→products) at several different concentrations of A.
What is the rate law for the reaction?
Rate = k[A]
Rate = k
Rate = k[A]3
Rate = k[A]4
If a reactant concentration is doubled and the reaction rate increases by a factor of 8, the exponent for that reactant in the rate law should be:
0
2
3
4
What is the correct Rate Law for this reaction?
rate=k[A]2[B]
rate=k[A][B]
rate=k[A]2[B]2
rate=k[A]3[B]
Given the following data for this reaction:
NH4+(aq) + NO2-(aq) --> N2(g) + 2H2O(l)
The rate law for the reaction is:
Rate = k[NH4+][NO2-]
Rate = k[NH4+]2[NO2-]2
Rate = k[NH4+]2[NO2-]
Rate = k[NH4+][NO2-]2
None of the above
Given: A + 3B --> 2C + D
This reaction is first order with respect to reactant A and second order with respect to reactant B. If the concentration of A is doubled and the concentration of B is halved, the rate of the reaction would _____ by a factor of _____.
increase, 2
decrease, 2
increase, 4
decrease, 4
The decomposition of carbon disulfide, CS2, to carbon monosulfide, CS, and sulfur, S, is first order with k = 2.8 x 10-7 s-1 at 1000oC.
CS2 --> CS + S
What is the half-life of this reaction at 1000°C?
5.0 x 107 s
4.7 x 10-6 s
3.8 x 105 s
6.1 x 104 s
2.5 x 106 s
The decomposition of dimethylether at 504 °C is first order with a half-life of 1570 seconds. What fraction of an initial amount of dimethylether remains after 4710 seconds?
1/3
1/6
1/8
1/16
1/32
When the concentration of reactant molecules is increased, the rate of reaction increases. The best explanation is: As the reactant concentration increases,
the average kinetic energy of molecules increases.
the frequency of molecular collisions increases.
the rate constant increases.
the activation energy increases.
the order of reaction increases.
Suppose the reaction: A + 2B --> AB2 occurs by the following mechanism:
Step 1: A + B --> AB Slow
Step 2: AB + B --> AB2 Fast
Overall: A + 2B --> AB2
The rate law expression must be rate = _________.
k[A]
k[B]
k[A][B]
k[B]2
k[A][B]2
A possible mechanism for the reaction, 2A + B --> C + D, is:
(1) A + A ⇌ A2 Fast
(2) A2 + A → A3 Slow
(3) A3 + B → A + C + D Fast
According to the mechanism, the rate law will be:
Rate = k[A]2
Rate = k[A][B]
Rate = k[A]2[B]
Rate = k[A]
Rate = k[A]3
At 300 K, the following reaction is found to obey the rate law: rate = k[NOCl]2: 2NOCl --> 2NO + Cl2
Consider the three postulated mechanisms given below. Then choose the response that lists all those that are possibly correct and no others.
2,3
3
1
2
1,2
For the reaction, 2H2S(g) + O2(g) --> 2S(s) + 2H2O(l), which one of the following statements is absolutely true?
The reaction is first order with respect to H2S and second order with respect to O2.
The reaction is fourth order overall.
The rate law is: rate = k[H2S]2[O2].
The rate law is: rate = k[H2S][O2].
The rate law cannot be determined from the information given.
Which one is the rate law expression for this elementary, gas phase reaction?
NO3 +CO → NO2 +CO2
rate = k[NO3]2
rate = k[CO]
rate = k[NO3]2[CO]2
rate = k[NO2][CO2]
rate = k[NO3][CO]
Which factor, if increased, will decrease the probability of a reaction occurring?
Molarity of the reactants
Complexity of the reactant particles
Energy of the reactant particles
Both a) and b)
If the temperature is increased, the peak of the curve will:
lower and shift to the left
lower and shift to the right
heighten and shift to the right
there will be no change in the shape of the curve.
According to collision theory, which of the following factors will not affect the probability of a given reaction occurring?
Relative alignment of the reactant particles
Speed at which the reactant particles are traveling
The change in energy from reactants to products
Energy of the reactant particles
A reaction with three reactant molecules will generally have ____ probability of occurring than a reaction with two reactant molecules.
less, because it will be harder to get three molecules to align than two
more, because the more reactants present, the greater the probability of molecules colliding
the same, because the only factors that affect collision rates are orientation and energy
it is impossible to make a judgement on this scenario without further information.
The activated complex is the _______, and is ________.
energy required to turn reactants into products; dependent on reactants’ orientation and energy
transition state between reactants and products; unstable due to half-formed, half-broken bonds
difference between the energy of the products and reactants; what determines if a reaction is exothermic or endothermic
substance formed by a catalyst that later becomes the products; also known as the intermediate
A reaction with a large activation energy will occur
quickly, because the increase in energy will increase the rate of reaction
at a rate dependent on other factors, as activation energy only describes the ΔE between products and reactants
quickly, because a large activation energy indicates an endothermic reaction, which has energy/heat as a reactant
slowly, because the molecules have to overcome a large energy barrier to for the activated complex
The difference in energy between products and reactants indicates
what effect temperature will have on reaction rate
the speed at which the reaction will occur
how many steps are in the reaction mechanism
the amount of energy needed to start the reaction
The reaction pictured in the diagram above is:
endothermic, uncatalyzed
exothermic, uncatalyzed
exothermic, catalyzed
endothermic, catalyzed
The mechanism above has been proposed for the reaction of CHCl3 with Cl2
Which of the following rate laws is consistent with this mechanism?
Rate = k[Cl2 ]
Rate = k[CHCl3] [Cl2]
Rate = k[CHCl3]
Rate = k[CHCl3] [Cl2] ½
Step 1: 2 NO2 (g) → N2 (g) + 2 O2 (g)
Step 2: 2 CO(g) + O2 (g) → 2 CO2 (g)
Step 3: N2 (g) + O2 (g) → 2 NO(g)
The above is a proposed mechanism for the reaction of NO2 and CO. What are the overall products of the reaction?
NO and CO2
O2 and CO2
N2 and NO
NO and O2
A reaction mechanism
is the sum of all steps in a reaction except the rate determining step.
has a ∆H equal to the ∆H for the most demanding step.
always has a rate determining step.
may be absolutely proven from the rate law.
is determined from the balanced expression only.
The mechanism for the reaction of nitrogen dioxide with carbon monoxide to form nitric oxide and carbon dioxide is thought to be:
NO2 + NO2 → NO3 + NO Slow
NO3 + CO → NO2 + CO2 Fast
What is the intermediate in the proposed mechanism?
NO3
CO
NO
CO2
A proposed mechanism for the reduction of nitrogen as NO by hydrogen is:
1) H2(g) + 2NO(g) → N2O(g) + H2O(g) (slow)
2) N2O(g) + H2(g) → N2(g) + H2O(g) (fast)
What is the rate law?
Rate = k[H2][NO]
Rate = k[H2]2[NO]
Rate = k[H2][NO]2
Rate = k[H2]2[NO]2
More information is needed to answer this question.
Select the correct sequence that corresponds to the numbers in the picture above.
Transition state 2 → Ea2 → △Hrxn< 0
Ea2 → Transition state 2 → △Hrxn< 0
Transition state 2 → Ea2 → △Hrxn> 0
Ea2 → △Hrxn> 0 → Transition state 2
Consider the following multistep reaction:
C+D ⇌ CD (fast)
CD+D → CD2 (slow)
CD2+D → CD3 (fast)
–––––––––––––––––––––
C+3D→CD3(overall)
Based on this mechanism, determine the rate law for the overall reaction.
k[C][D]3
k[D][CD]
k[C][D]2
k[C][D]
Step1: A+B ⇌ C (fast)
Step2: B+C → D (slow)
Express the rate law of the overall reaction in terms of k and the necessary concentrations.
rate = k[B][C]
rate = k[B]2[C]
rate = k[B]2[A]
rate = k[B][A]
Solutions each with a Y concentration of 1.0 μM and varying concentrations of AB as shown below. Based on the concentrations, which solution has the highest reaction rate.
0.5 μM AB
0.6 μM AB
0.7 μM AB
All of the concentration above has the same reaction rate.
Which of the following, when added to a solution containing 1.0 μM Y and 0.8 μM AB, will result in an increase in reaction rate?
More AB
More A
An inhibitor
More Y
Select the correct sequence that corresponds to the numbers in the picture above.
Ea1 → Reaction intermediate → Transition state 1
Reaction intermediate → Ea2 → Transition State 2
Ea2 → Reaction intermediate → Transition state 1
Ea1 → Transition state 1 → Reaction intermediate
What is the rate law for the uncatalyzed reaction?
rate = k[Ce4+]2[Tl+]2
rate = k[Ce4+]2[Tl+]
rate = k[Ce4+][Mn2+]
rate = k[Ce4+][Tl+]2
Consider the following multistep reaction:
1. 2 NO(g) ⇌ N2O2 (g) Fast
2. H2(g) + N2O2(g) → H2O(g) + N2O(g) Slow
3. H2(g) + N2O(g) → H2O(g) + N2 (g) Fast
Based on this mechanism, determine the rate law for the overall reaction.
k[N2][N2O2]
k[H2]2[NO]
k[H2][NO]2
k[H2]2[NO]2
Of the following, __________ will lower the activation energy for a reaction.
increasing the concentrations of reactants
adding a catalyst for the reaction
raising the temperature of the reaction
removing products as the reaction proceeds
Which of the following hold reactant molecules in proper orientation for reaction to occur?
Heterogeneous catalysts
Homogeneous catalysts
