Assertion: For the change, H2O(l) → H2O(s), Δ H = Δ U. Reason: No enthalpy change is involved in this process.

Question

Assertion: For the change, H2O(l) → H2O(s), Δ H = Δ U. Reason: No enthalpy change is involved in this process. (A) If both assertion and reason are true and reason is the correct explanation of assertion (B) If both assertion and reason are true but reason is not the correct explanation of assertion (C) If assertion is true but reason is false (D) If both assertion and reason are false

Tardigrade Admin · Accepted Answer

For the change, H2O(l) → H2O(s), there is negligible change in volume. ∴ P Δ V = Δ ngRT ≈ 0 Now, substituting the above value in eqn Δ H = Δ U + Δ ngRT we get, Δ H = Δ U.

Q. Assertion : For the change, $H_{2} O_{(l)} \to H_{2} O_{(s)}$ , $Δ H = Δ U$ .
Reason : No enthalpy change is involved in this process.

If both assertion and reason are true and reason is the correct explanation of assertion

If both assertion and reason are true but reason is not the correct explanation of assertion

If assertion is true but reason is false

If both assertion and reason are false

For the change, $H_{2} O_{(} l) \to H_{2} O_{(s)}$ , there is negligible change in volume.
$∴ P Δ V = Δ n_{g} RT \approx 0$
Now, substituting the above value in eqn
$Δ H = Δ U + Δ n_{g} RT$
we get, $Δ H = Δ U$ .

Q. Assertion : For the change, H2​O(l)​→H2​O(s)​, ΔH=ΔU. Reason : No enthalpy change is involved in this process.