Question

What is the effect of adding more CO2 to the following equilibrium reaction? CO2 + H2O H2CO3

A. More H2CO3 is produced.
B. More H2O is produced.
C. The equilibrium is pushed in the direction of reactants.
D. no change

Also, 

Which of the following is the correct expression for the rate of the following reaction? Note: All species are gaseous.

2SO3 <--> 2SO2 + O2

A. [SO3]2 / ([SO2]2 x [O2])  
B. [SO2]2 x [O2] / [SO3]

 
C. [SO2]2 x [O2] / [SO3]2  
D. [SO2] x [O2] / [SO3]

Answer 1

Answer: 1) A. More H2CO3 is produced.

2) C.
`K=([SO_2]^2*[O_2])/([SO_3]^2)`

Explanation:1) Any change in the equilibrium is studied on the basis of Le-Chatelier's principle.

This principle states that if there is any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.

`CO_2+H_2O\rightarrow H_2CO_3`

If concentration of
`CO_2` is increased, that is the reactant is increased, so according to the Le-Chatlier's principle, the equilibrium will shift in the direction where decrease of concentration of
`CO_2` takes place. Therefore, the equilibrium will shift in the right direction, i.e.
`H_2CO_3` will be formed.

2) The rate of a equilibrium reaction is determined by equilibrium constant. Equilibrium constant is the ratio of the product of the concentration of products to the product of the concentration of reactants each term raised to their stochiometric coefficients.

`2SO_3\rightarrow 2SO_2+O_2`

`K=([SO_2]^2* [O_2])/([SO_3]^2)`

Answer 2

1.) Adding CO2 creates a stress on the equlibrium system.which means there will be exothermic reaction in other words more product (i:e H2CO3) will be formed.

The equilibrium will shift to the right to offset the applied stress.

Hence more H2CO3 will be produced. Option A is correct.




2.) Rate = [SO2]2 x [O2] / [SO3]2.

Hence option C is correct.

Hope this helps!