Question

During chemical weathering, forsterite is dissolved by the carbonic acid in rainwater. The weathering reaction is as follows:

Mg2SiO4 forsterite + 4H2CO3 (aq) → 2Mg^2+ + 4HCO3- + H4SIO4 (aq)

Rrquired:
Calculate the Keq. Units are NOT required.

Answer 1

Keqq = 310

Note: Some parts of the question were missing. The missing values are used in the explanation below.

Step-by-step explanation:

Given values: ΔH° = -178.8 kJ/mol = -178800 J/mol; T = 25°C = 298.15 K; ΔS° = -552 J/mol.K; R = 8.3145 J/mol.K

Using the formula ΔG° = -RT㏑Keq

㏑Keq = ΔG°/(-RT)

where ΔG° = ΔH° - TΔS°

㏑Keq = ΔH° - TΔS°/(-RT)

㏑Keq = {-178800 - (-552 * 298.15)} / -(8.3145 * 298.15)

㏑Keq = -14221.2/-2478.968175

㏑Keq = 5.73674166

Keq = e⁵°⁷³⁶⁷⁴¹⁶⁶

Keq = 310.05