A solution of calcium chloride (Mr=111.0M_{\text{r}} = 111.0Mr=111.0) contains 1.39 g of CaCl2\text{CaCl}_2CaCl2 in 200 cm3 of solution. In this solution, the calcium chloride is fully dissociated into ions.
What is the concentration of chloride ions in this solution?
1.25×10−2 mol dm−31.25 \times 10^{-2}\text{ mol dm}^{-3}1.25×10−2 mol dm−3
2.50×10−2 mol dm−32.50 \times 10^{-2}\text{ mol dm}^{-3}2.50×10−2 mol dm−3
6.26×10−2 mol dm−36.26 \times 10^{-2}\text{ mol dm}^{-3}6.26×10−2 mol dm−3
1.25×10−1 mol dm−31.25 \times 10^{-1}\text{ mol dm}^{-3}1.25×10−1 mol dm−3