Home
Class 12
CHEMISTRY
K(p) for a reaction at 25^(@)C is 10 atm...

`K_(p)` for a reaction at `25^(@)C` is `10` atm. The activation energy for forward and reverse reactions are `12` and `20 kJ mol^(-1)` respectively. The `K_(c)` for the reaction at `40^(@)C` will be:

A

`4.33 xx 10^(-1)` M

B

`3.33 xx 10^(-2)` M

C

`3.33 xx 10^(-10)`M

D

`4.33 xx 10^(-2)` M

Text Solution

Verified by Experts

The correct Answer is:
C
Enthalpy changed of a reaction is given by
`DeltaH=E_(a(f))-E_(a(b))`
where `E_(a(f)) and E_(a(b))` are energies of activation for the forward and backward reactions.
`DeltaH=12 -20 =-8 kJ //mol`
`K_p` for the reaction at `25^@C -10` atm. Since `K_p` is expressed in atmoshere, `Deltan=+1`
`because K_p =K_c(RT)^(Deltan), K_c=(10)/(0.0821xx298)=0.4 M`
`K_c "at" 40^@C` is given by
`log""(k_c)_(40)/(K_c)_(25)=(DeltaH)/(2.303R)[1/(T_1)-1/(T_2)]=(-8xx1000)/(2.303xx8.314)xx(15)/(298xx313)=-0.06719`
`(K_c)_(40)//(K_c)_(25)=0.85`
`(K_c)_(40)=0.85xx0.4 =0.34M`
Promotional Banner

Similar Questions

Explore conceptually related problems

A reaction having equal energies of activation for forward and reverse reactions has

A reaction having equal energies of activation for forward and reverse reactions has

The activation energies of the forward and backward reactions in the case of a chemical reaction are 30.5 and 45.4kJ/mol respectively. The reaction is:

The activation energies of the forward and backward reactions in the case of a chemical reaction are 37.5 and 51.3 kJ/mole respectively The reaction is

For the reaction A+B hArr C , the rate constants for the forward and the reverse reactions are 4xx10^(2) and 2xx10^(2) respectively. The value of equilibrium constant K for the reaction would be

In a hypothetical reaction X to Y , the activation energy for the forward backward reactions are 15 and 9 kJ mol^(-1) respectively. The potential energy of X is 10 kJ mol^(-1) . Which of the following statement is/are correct? (i) The threshold energy of the reaction is 25 kJ mol^(-1) (ii) The potential energy of Y is 16 kJ mol^(-1) (iii) Heat of reaction is 6 kJ mol^(-1) The reaction is endothermic.

For the reversible reaction, A+BhArrC , the specific reaction rates for forward and reverse reactions are 1.25xx10^(3) "and" 2.75xx10^(4) respectively. The equilibrium constant for the reaction is:

The activation energy for the forward reaction X rarr Y is 60 kJ mol^(-1) and Delta H is -20 kJ mol^(-1) . The activation energy for the reverse reaction is

If the activation energies of the forward and backward reactions of a reversible reaction are E_(a)(f) and E_(a)(b) , respectively. The DeltaE of the reaction is ………..

A colliison between reactant molecules must occur with a certain minimum energy before it is effective in yielding Product molecules. This minimum energy is called activation energy E_(a) Large the value of activation energy, smaller the value of rate constant k . Larger is the value of activation energy, greater is the effect of temperature rise on rate constant k . E_(f) = Activation energy of forward reaction E_(b) = Activation energy of backward reaction Delta H = E_(f) - E_(b) E_(f) = threshold energy The activation eneries for forward and backward reactions in a chemical reaction are 30.5 and 45.4 kJ mol^(-1) respectively. The reaction is