Chapter 17 Revision

Definitions

100

The minimum amount of energy needed to start a reaction is called the

Activation energy

200

Substance that speeds up the rate of chemical reaction without itself being changed

Catalyst

300

Reaction involving reactants and products in the same state.

Homogeneous reactions

400

Reaction involving reactants and products in different states.

Heterogeneous reaction

500

is a dynamic state where the concentrations of the reactants and products remain constant over time, as long as the conditions are not changed.

Chemical equilibrium 

Questions Part 1

100

What happens to a catalyst in a reaction?  

Remains unchanged

200

For the reaction  N2   +  3H2  ---->  2 NH3, the correct equilibrium expression is____

[NH3]2 / [N2][H2]3

300

For the reaction F2(g) --->  2F(g), at a particular temperature, the concentration at equilibrium were observed to be [F2] = 1.0 x 10-2 mol/L and [F] = 2.0 x 10-4 mol/L. Calculate the value of the equilibrium constant from these data.

4.0 x 10^-6

400

While calculation the equilibrium constant, each concentration is raised to a power corresponding to its__________

Coefficient

500

There is only one equilibrium constant for a particular system at a particular temperature. 

True/ False

True

Questions Part 2

100

Equilibrium constant does not depend on the concentrations. 

True/ False

True

200

If the pressure on the equilibrium system 2CO (g) + O2 (g)  <---->    2CO2 (g) is increased, the amount of CO2 will __________

increase

300

. If the temperature of the equilibrium system  

CH3OH (g) + 101 kJ   <-----> CO (g) + 2H2 (g) increases, the amount of CH3OH will ________ and the amount of CO will _________

[CH3OH] decreases and [CO] increases.

400

List the five factors that affect the rate of reaction.

1. Concentration 

2. Surface area 

3. Temperature 

4. Catalyst  

5. nature of the reactants

500

When concentration of reactants increases, equilibrium shifts towards the__________

Product

Questions Part 3

100

When concentration of reactants decreases, the equilibrium shifts towards the_________

The reactants

200

Decrease in volume of a gas causes increase in pressure, so the equilibrium favors the side with______

Fewer gas moles

300

Increase in volume of a gas causes decrease in pressure, so the equilibrium favors the side with__________

more gas moles

400

A reaction that produces heat is called_____

Exothermic reaction

500

A reaction that absorbs here to occur is called_____

Endothermic reaction

Questions Part 4

100

-When temperature is increased, the _________ reaction is favored. 

Endothermic / Exothermic

Endothermic 

200

-When temperature is decreased, the _________ reaction is favored. 

Endothermic / Exothermic

Exothermic 

300

Given the reaction at equilibrium   

 C(s)  +  O2(g)  <---> CO2(g)  + heat, which stress on the system will increase the concentration of CO2 (g)?

a. Increasing the temperature of the reaction

b. Increasing the concentration of O2(g)                

c. Decreasing the pressure on the reaction

d. Decreasing the amount of C (s)

b. Increasing the concentration of O2(g)    

400

If the pressure on gaseous reactants is increased, the rate of reaction is increased because there’s an increase in the_________

Number of particles per unit volume

500

Given the exothermic reaction at equilibrium  

  A(g)  +  2B(g)  <--->  C(g) +Cl- (aq), which of the following will sift the reaction equilibrium towards the products? 

a. Raising the temperature      

b. Adding more C (g)

c. Decreasing the volume            

d. Removing some A (g)

c. Decreasing the volume