MCQ
The relation between equilibrium constant ${K_p}$ and ${K_c}$ is
  • A
    ${K_c} = {K_p}\,{(RT)^{\Delta n}}$
  • ${K_p} = {K_c}{(RT)^{\Delta n}}$
  • C
    ${K_p} = {\left( {\frac{{{K_c}}}{{RT}}} \right)^{\Delta n}}$
  • D
    ${K_p} - {K_c} = {(RT)^{\Delta n}}$

Answer

Correct option: B.
${K_p} = {K_c}{(RT)^{\Delta n}}$
b
Let the gaseous reaction is a state of equilibrium is-

$aA _{( g )}+ bB _{( g )} \rightleftharpoons cC _{( g )}+ dD _{( g )}$

Let $p _{ A }, p _{ B }, p _{ C }$ and $p _{ D }$ be the partial pressure of $A , B , C$ and $D$ repectively. Therefore,

$K _{ c }=\frac{[ C ]^{ c }[ D ]^{ d }}{[ A ]^{ a }[ B ]^{ b }} \ldots . .(1)$

$K _{ p }=\frac{ pC ^c p _{ D }^{ d }}{ p _{ A }^{ a } p _{ B }^{ b }} \ldots \ldots .(2)$

For an ideal gas-

$PV = nRT$

$\Rightarrow P =\frac{ n }{ V } RT = CRT$

Whereas $C$ is the concentration.

Therefore,

$p _{ A }=[ A ] RT$

$p _{ B }=[ B ] RT$

$p _{ C }=[ C ] RT$

$p _{ D }=[ D ] RT$

Substituting the values in equation $(2),$ we have

$K _{ p }=\frac{[ C ]^{ c }( RT )^{ c }[ D ]^{ d }( RT )^{ d }}{[ A ]^{ a }( RT )^{ a }[ B ]^{ b }( RT )^{ b }}$

$\Rightarrow K _{ p }=\frac{[ C ]^{ c }[ D ]^{ d }}{[ A ]^{ a }[ B ]^{ b }}( RT )^{[( c c )-( a + b )]}$

$\left.\Rightarrow K _{ p }= K _{ c }( RT )^{\Delta n_{ g }} \quad \text { (From (1) }\right]$

Here,

$\Delta n _{ g }=$ Total no. of moles of gaseous product $-$ Total no. of moles of gaseous reactant

Hence the relation between $K_p$ and $K_c$ is-

$K _{ p }= K _{ c }( RT )^{\Delta n _{ g }}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

The presence of the chlorine atom on benzene ring makes the second substituent enter at a position
$[ X ]+ H _2 SO _4 \rightarrow[ Y ]$ a colourless gas with irritating smell
$[ Y ]+ K _2 Cr _2 O _7+ H _2 SO _4 \rightarrow$ green solution [X] and [Y] is
Products $A$  and $B$  formed in the following reactions are respectively

$[Figure]$  $\longrightarrow \,\,A\,\xrightarrow{{{C_6}{H_5}N{H_2}}}B$

What is product of the following reaction ?
The hydrolysis of an ester was carried out separately with $0.1\ N$ $HCl$ and $0.1\ N$ $H_2SO_4$ . Then for rate of reaction $(R)$ in the presence of acid which of the following relation is true
On complete combustion $1.4 \,gm$ hydrocarbon gave $1.8\, gm$ water. Empirical formula of the hydrocarbon is
Which one of the following alcohols reacts instantaneously with Lucas reagent?
The decreasing order of reactivity of given compound towards nucleophilic  substitution with aqueous $NaOH$ is
$B$ has a smaller first ionization enthalpy than $Be$. Consider the following statements :

$(I)$ It is easier to remove $2 \mathrm{p}$ electron than $2 \mathrm{s}$ electron

$(II)$ $2 \mathrm{p}$ electron of $\mathrm{B}$ is more shielded from the nucleus by the inner core of electrons than the $2 s$ electrons of $Be.$

$(III)\; 2 s$ electron has more penetration power than $2 \mathrm{p}$ electron.

$(IV)$ atomic radius of $\mathrm{B}$ is more than $\mathrm{Be}$

(Atomic number $\mathrm{B}=5, \mathrm{Be}=4$ )

The correct statements are

When propionamide reacts with $Br_2$ in the presence of alkali the product is :