What is the value of q when the solution contains 2.50*10-3 m mg2 + and 2.00*10-3m co32-? express your answer numerically?

Answer is: value of Q is 5·10⁻⁶M.

Chemical reaction: Mg²⁺ (aq) + CO₃²⁻ (aq) → MgCO₃ (s).

c (Mg²⁺) = 2.5·10⁻³ M; concentration of magnesium cations.

c (CO₃²⁻) = 2.00·10⁻³ M; concentration of carbonate anions.

Q = c (Mg²⁺) · c (CO₃²⁻).

Q = 2.5·10⁻³ M · 2.00·10⁻³ M.

Q = 5·10⁻⁶M.

Q = 0.000005 M.