`H_(2)(g) + Ar(g) underset(k_(r ))overset(k_(f))hArr 2H(g)+Ar(g)`
`k_(f)= 2.2xx10^(4)Lmol^(-1)s^(-1)` and `k_(c )= 1.02xx10^(-4)` at `3000 K`. What is the value of `k_(r )`?

Explanation

To find the value of \( k_r \) (the rate constant for the backward reaction), we can use the relationship between the forward rate constant (\( k_f \)), the backward rate constant (\( k_r \)), and the equilibrium constant (\( K_c \)).

### Step-by-Step Solution:

1. **Identify the given values:**
- Forward rate constant, \( k_f = 2.2 \times 10^4 \, \text{L mol}^{-1} \text{s}^{-1} \)
- Equilibrium constant, \( K_c = 1.02 \times 10^{-4} \)

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