Calculate the concentration of chromate ion (CrO₄^2-) in a 0.450 M solution of chromic acid (H₂CrO₄). [For chromic acid, K_a1 = 0.18, K_a2 = 3.2 * 10^-7.] A) 3.2 * 10^-7 M B) 1.5 * 10^-6 M C) 0.081 M D) 1.1 * 10^-6 M E) 0.21 M

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The concentration of chromate ion (CrO4^2-) in a solution of chromic acid (H2CrO4) can be calculated using the second dissociation constant (Ka2) of chromic acid, which is given as 3.2 × 10^-7. This constant represents the equilibrium concentration of H+, CrO4^2-, and HCrO4^- ions in solution. Since Ka2 is directly related to the formation of CrO4^2- from HCrO4^-, and given that the concentration of chromic acid is 0.450 M, the concentration of CrO4^2- will be significantly lower than the initial concentration of H2CrO4 due to the small value of Ka2. However, the correct concentration of CrO4^2- is directly given as 3.2 × 10^-7 M, which corresponds to the Ka2 value, indicating the equilibrium concentration of chromate ions under the assumption that it dissociates completely in the second step, which is a simplification for the purpose of this calculation.

Calculate the Concentration of Chromate Ion (CrO42-) in a 0

Calculate the Concentration of Chromate Ion (CrO₄^2-) in a 0