Salt preparations
3 marks · EasyA student wants to prepare a pure, dry sample of lead(II) sulfate in the laboratory.
State whether lead(II) sulfate is soluble or insoluble in water.
Name two solutions that could be mixed to produce lead(II) sulfate.
Describe one step the student must take after mixing the solutions to obtain a pure, dry sample of the salt.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) Insoluble
(b) Any suitable pair, e.g., lead(II) nitrate and sodium sulfate
(c) Filter the mixture to separate the precipitate, then dry the solid.
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · States that lead(II) sulfate is insoluble.
B1 (b) · 1 mark · Names two suitable solutions (e.g. lead(II) nitrate and sodium sulfate, or lead(II) nitrate and potassium sulfate).
B1 (c) · 1 mark · Describes filtration and/or drying to obtain pure, dry salt.
Worked solution
(a) Lead(II) sulfate is insoluble in water.
(b) Mix solutions of lead(II) nitrate and sodium sulfate.
(c) Filter the mixture to separate the solid lead(II) sulfate, wash it with water, and dry the residue.