Calculate the equilibrium pressure (in bar) for the conversion of calcite to aragonite at 2 5 ∘ C . The densities of calcite and aragonite may be taken as 2.50 and 3.00 g/cc respectively, independent

Question

Calculate the equilibrium pressure (in bar) for the conversion of calcite to aragonite at $2 5^{\circ} C$ . The densities of calcite and aragonite may be taken as 2.50 and 3.00 g/cc respectively, independent of pressure. Molar mass of $CaCO_{3} = 100$ g/mol. ( $1 bar = 1 0^{5} Pa$ )

Given $Δ G_{298}^{\circ}$ (calcite $\to$ aragonite) $= 1000 J/mol$ .

TestHub · Accepted Answer

At equilibrium Δ G = Δ G ∘ + P Δ V = 0 (taking the reference pressure as negligible). Δ V = 100 ( 3.00 1 ​ − 2.50 1 ​ ) c m 3 /mol = − 6.67 c m 3 /mol = − 6.67 × 1 0 − 6 m 3 /mol . P = 6.67 × 1 0 − 6 1000 ​ = 1.5 × 1 0 8 Pa = 1500 bar . Answer: 1500.

Chemistry - Thermodynamics - II Question with Solution | TestHub

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