As we know, K_p = K_c × (RT)^$\Delta$n_g

So, for reaction having same number of gaseous moles on reactants and products side will have same value of Kc and Kp otherwise their values are different.

For reaction, 2NO_(g) $\rightleftharpoons$ N_2(g) + O_2(g)

$\Delta$n_g = 2 – 2 = 0

$\Rightarrow$ K_p = K_c × (RT)⁰

$\therefore$ K_p = K_c

For reaction, SO_2(g) + NO_2(g) $\rightleftharpoons$ SO_3(g) + NO_(g)

$\Delta$n_g = 2 – 2 = 0

$\Rightarrow$ K_p = K_c × (RT)⁰

$\therefore$ K_p = K_c

For reaction, H_2(g) + I_2(g) $\rightleftharpoons$ 2HI_(g)

$\Delta$n_g = 2 – 2 = 0

$\Rightarrow$ K_p = K_c × (RT)⁰

$\therefore$ K_p = K_c

For reaction, H_2(g) + I_2(g) $\rightleftharpoons$ 2HI_(g)

$\Delta$n_g = 2 – 2 = 0

$\Rightarrow$ K_p = K_c × (RT)⁰

$\therefore$ K_p = K_c

For reaction, 2C_(s) + O_2(g) $\rightleftharpoons$ 2CO_2(g)

$\Delta$n_g = 2 – 3 = -1

$\Rightarrow$ K_p = K_c × (RT)^-1

$\therefore$ K_p $\ne$ K_c