Answer:
0.750 g
Explanation:
The reaction that takes place is:
- CaS (aq) + (NH₄)₂CO₃ (aq) → CaCO₃ (s) + (NH₄)₂S (aq)
First we calculate how many moles of each reactant were added, using the given volumes and concentrations:
- CaS ⇒ 50 mL * 0.15 M = 7.5 mmol CaS
- (NH₄)₂CO₃ ⇒ 30 mL * 0.35 M = 10.5 mmol (NH₄)₂CO₃
Given that they react in a 1:1 ratio, and that there are less CaS moles than (NH₄)₂CO₃ moles, CaS is the limiting reactant.
- 7.5 mmoles of CaS will produce 7.5 mmoles of CaCO₃.
We now convert 7.5 mmol CaCO₃ into mg, using its molar mass:
- 7.5 mmol * 100 mg/mmol = 750 mg
Finally we convert 750 mg to g:
