Hydrated copper(II) chloride can be prepared by reacting excess copper(II) carbonate with dilute hydrochloric acid.
The equation for the reaction is:
CuCO3(s)+2HCl(aq)→CuCl2(aq)+H2O(l)+CO2(g) \text{CuCO}_3(\text{s}) + 2\text{HCl}(\text{aq}) \rightarrow \text{CuCl}_2(\text{aq}) + \text{H}_2\text{O}(\text{l}) + \text{CO}_2(\text{g}) CuCO3(s)+2HCl(aq)→CuCl2(aq)+H2O(l)+CO2(g)In one experiment, a sample of 0.050 mol0.050\text{ mol}0.050 mol of $\text{CuCO}_3isaddedtois added toisaddedto0.080\text{ mol}ofofof \text{HCl} .Show,bycalculation,thatthe. Show, by calculation, that the .Show,bycalculation,thatthe\text{CuCO}_3$ is in excess.
Calculate the maximum volume, in cm3\text{cm}^3cm3, of carbon dioxide, measured at room temperature and pressure (RTP), that would be obtained when 0.080 mol0.080\text{ mol}0.080 mol of HCl\text{HCl}HCl reacts completely with CuCO3\text{CuCO}_3CuCO3.
One mole of any gas occupies 24,000 cm3 at room temperature and pressure. \text{One mole of any gas occupies } 24,000\text{ cm}^3\text{ at room temperature and pressure.} One mole of any gas occupies 24,000 cm3 at room temperature and pressure.In another experiment, 0.050 mol0.050\text{ mol}0.050 mol of CuCO3\text{CuCO}_3CuCO3 reacts with excess HCl\text{HCl}HCl. A yield of 5.8 g5.8\text{ g}5.8 g of hydrated copper(II) chloride crystals, CuCl2⋅2H2O\text{CuCl}_2 \cdot 2\text{H}_2\text{O}CuCl2⋅2H2O, is obtained.
Calculate the percentage yield of CuCl2⋅2H2O\text{CuCl}_2 \cdot 2\text{H}_2\text{O}CuCl2⋅2H2O.
Relative atomic masses, Ar: Cu=63.5; Cl=35.5; H=1; O=16. \text{Relative atomic masses, } A_r\text{: Cu} = 63.5\text{; Cl} = 35.5\text{; H} = 1\text{; O} = 16\text{.} Relative atomic masses, Ar: Cu=63.5; Cl=35.5; H=1; O=16.Suggest one practical reason why the percentage yield of CuCl2⋅2H2O\text{CuCl}_2 \cdot 2\text{H}_2\text{O}CuCl2⋅2H2O crystals is less than 100%100\%100%.
80 exam-style questions on Edexcel IGCSE Chemistry Chemical formulae, equations and calculations. Each one has a worked solution and a mark scheme showing where the marks go.