3.75 g of a mixture of `CaCO_3` and `MgCO_3` is dissolved in 1 L of 0.1 M HCl to liberate 0.04 " mol of "`CO_2`. Calculate
(a). The percentage of each compound in the mixture.
(b). The amound of acid used.
(c). The amound of acid left after the reaction.

Explanation

To solve the problem step-by-step, we will break it down into parts (a), (b), and (c) as requested.

### Given Data:
- Total mass of the mixture (CaCO₃ and MgCO₃) = 3.75 g
- Molarity of HCl = 0.1 M
- Volume of HCl solution = 1 L
- Moles of CO₂ liberated = 0.04 mol

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