The solubility of a salt in water decides how it is prepared. Table 4.1 gives some solubility rules. Type of salt Solubility in water all sodium salts solub...
Question 1 Report
The solubility of a salt in water decides how it is prepared. Table 4.1 gives some solubility rules.
| Type of salt | Solubility in water |
|---|---|
| all sodium salts | soluble |
| all nitrates | ................ |
| chlorides (except silver and lead) | ................ |
| most carbonates | ................ |
(a) Complete Table 4.1 using the word soluble or insoluble in each blank cell. [3]
(b) Use the rules to predict whether each of these salts is soluble or insoluble in water.
(i) silver chloride (ii) barium sulfate (iii) sodium carbonate [3]
(c) Name the method used to prepare an insoluble salt. [1]
(d) Explain why this method cannot be used to prepare sodium chloride. [2]
Answer Details
What this tests: applying solubility rules and knowing which preparation method suits a soluble or insoluble salt.
(a) Completed Table 4.1 [3] all nitrates = soluble; chlorides (except silver and lead) = soluble; most carbonates = insoluble [1 each].
(b) Predictions [3] (i) silver chloride = insoluble [1] (silver is one of the chloride exceptions); (ii) barium sulfate = insoluble [1]; (iii) sodium carbonate = soluble [1] (all sodium salts are soluble, which overrides the carbonate rule).
(c) [1] An insoluble salt is made by precipitation (mixing two soluble solutions so the insoluble salt drops out).
(d) [2] Sodium chloride is soluble in water [1]; so no precipitate forms - the ions stay dissolved and cannot be filtered off, so precipitation cannot be used [1].
Download The App On Google Playstore
Everything you need to excel in your exams
