WAEC (WASSCE) Chemistry · Solutions, energy and chemical change
Solubility of substances: WAEC Chemistry Past Questions and Answers
What the WAEC syllabus covers in Solubility of substances
Our summary: How much of a substance dissolves, solubility curves and calculations, and how solubility rules help identify ions.
- General principles ((1) Meaning of solubility. (2) Saturated and unsaturated solutions. (3) Saturated solution as an equilibrium system. (4) Solubility expressed in terms of: mol dm⁻³ and g dm⁻³ of solution/solvent. (5) Solubility curves and their uses. (6) Effect of temperature on solubility of a substance. (7) Relationship between solubility and crystallization. (8) Crystallization/recrystallization as a method of purification. (9) Knowledge of soluble and insoluble salts of stated cations and anions. (10) Calculations on solubility.)
- Practical application of solubility (Generalization about solubility of salts and their applications to qualitative analysis, e.g. Pb²⁺, Ca²⁺, Al³⁺, Cu²⁺, Fe²⁺, Fe³⁺, Cl⁻, Br⁻, I⁻, SO₄²⁻, S²⁻, and CO₃²⁻, Zn²⁺, NH₄⁺, SO₃²⁻. Explanation of solubility rules.)
Syllabus content © The West African Examinations Council (WASSCE (harmonised West African syllabus)).
WAEC (WASSCE) Chemistry questions on Solubility of substances
- WAEC 2024A saturated solution at 30 ^0 C will normally produce crystals at a temperature of
- WAEC 2024At 25 ^0 C, the saturated solution of a salt in water was found to contain 0.24g of the salt in 100cm ^3 . What is the solubility of the salt in gdm ^ -1 ?
- WAEC 2023If 100^3 of a saturated solution of sodium tetraoxosulphate (VI) at 30° C contains 10.5 g of the salt, what would be its solubility at this temperature? [( Na…
- WAEC 2023A mixture containing two salts of different solubility can be separated by
- WAEC 2022If 50 cm ^ 3 of a saturated solution of KNO 3 at 40 °C contained 5.05 g of the salt, its solubility at the same temperature would be [KNO 3 = 101]
- WAEC 2022Increasing the temperature generally
- WAEC 2021The 25°C evaporation of a 100 cm ^ 3 solution of K 2 CO 3 to dryness gave 14g of the salt. What is the solubility of K 2 CO 3 at 25°C? [K 2 CO 3 = 138]
- WAEC 2021Which of the following pairs of compounds would form a precipitate when their aqueous solutions are mixed?
- WAEC 2021Which of the following gasses is highly soluble in water at room temperature
- WAEC 2020The high solubility of ethanol in water is due to?
- WAEC 2020Which of the following hydroxides is not readily soluble in water?
- WAEC 2020Which of the following statements about the solubility of a salt is correct?
- WAEC 2020When 250 cm3 of a saturated solution of CuSO 4 at 30°C was evaporated to dryness, 5.0 g of the salt was obtained.. What is the solubility of the salt at 30°C?…
- WAEC 2019What is the solubility of a salt X at 25ºC if the saturated solution of the salt contains 0.28g in 100cm ^3 of the solution in mol ^3 ? [ X = 56.0g ]
- WAEC 2019When an equilibrium is established between dissolved and undissolved solutes, the solution is said to be?
- WAEC 2018The solubility of CO 2 in water can be accounted for by
- WAEC 2018When a salt is added to its saturated solution, the salt
- WAEC 2018What is the solubility of a salt if 0.4g of it is obtained on evaporating 200 cm^ 3 of its saturated solution to dryness?
- WAEC 2017If 0.2g of a salt is required to saturate 200 cm^ 3 of water at room temperature, what is the solubility of the salt?
- WAEC 2017In a saturated solution at a given temperature, the undissolved solutes are in equilibrium with
- WAEC 2016An unsaturated solution differs from a saturated solution at a given temperature because it
- WAEC 2016On evaporation to dryness, 350cm ^3 of saturated solution of salt Z gave 55.5g of salt. What is the solubility of the salt? [Z = 101]
- WAEC 2015Solubility is practically applied in
- WAEC 2015Which of the following compounds is the least soluble in water?
- WAEC 2015A change in the temperature of a saturated solution disturbs the equilibrium between the
- WAEC 2013The following factors affect the solubility of a solid in a given solvent except
- WAEC 2012MgO does not readily dissolve in water because
- WAEC 2011On evaporation to dryness, 250 cm3 of saturated solution of salt X with relative molar mass 101 gave 50.5g of the. What is the soluility of the salt?
- WAEC 2010Which of the following chlorides is insoluble in water?
- WAEC 2010Which of the following factors would not affect the solubility of a gas?
Years with Solubility of substances questions in DeeepSolve's question bank
From the past questions DeeepSolve holds, not a count of everything the exam body has set.
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