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1jmoore
May 15, 2010, 07:38 PM
Find the Qsp when 5 drops of 0.0019 M
K2CO3(aq) are added to 15 mL of 0.0022 M
CaCl2(aq). The solubility product of CaCO3
Is 8.7 × 10−9. Assume 20 drops per milliliter.

Unknown008
May 19, 2010, 07:22 AM
Write your equations...

K_2CO_3 + CaCl_2 \rightarrow CaCO_3 + 2KCl

CaCO_3 \rightleftharpoons Ca^{2+} + CO_3 \ ^{2-}

The Ksp of CaCO3 is given by:

K_{sp} = \frac{[Ca^{2+}][CO_3\ ^{2+}]}{[CaCO_3]} = 8.7 \times 10^{-9}

The Qsp of CaCO3 is given by:

Q_{sp} = [Ca^{2+}][CO_3\ ^{2+}]

To get your answer, find the number of moles of CaCO3 formed from the given data and the equation for the reaction.

Use the Ksp expression to find the number of moles of Ca^2+ and CO3 ^2-. Once you get those, you can find the Qsp.

Do you still have problems? If so, post back.