Chemistry · BGCSE / Air, water and the environment
StructuredPast exam questionForm 5 · BGCSE
Water containing dissolved carbon dioxide reacts with limestone, CaCO₃, forming hard water as shown by the equation. H₂O(l) + CO₂(g) + CaCO₃(s) → Ca(HCO₃)₂(aq)
- aName the type of hardness in the water resulting from the reaction. [1]
- bApart from the calcium ion, Ca²⁺, state another ion that makes water hard. [1]
- cState two methods of softening hard water. [2]
You'll mark your own answer against the marking guide when you hand it in.
Source: BEC BGCSE Chemistry 2013, Paper 3, Question 1(d)
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