For the following Assertion and Reason, the correct option is
Question:

For the following Assertion and Reason, the correct option is

Assertion (A) : When Cu (II) and sulphide ions are mixed, they react together extremely quickly to give a solid.

Reason $(\mathbf{R}):$ The equilibrium constant of

$\mathrm{Cu}^{2+}(\mathrm{aq})+\mathrm{S}^{2-}(\mathrm{aq}) \rightleftharpoons \mathrm{CuS}(\mathrm{s})$

is high because the solubility product is low.

1. Both $(A)$ and $(R)$ are true and $(R)$ is the explanation for (A)

2. Both (A) and (R) are false

3. (A) is false and (R) is true

4. Both (A) and (R) are true but (R) is not the explanation for (A)

Correct Option: , 4

Solution:

Slow or fast process is kinetic parameter but extent less or more is thermodynamic parameter.