Making salts Insoluble base and precipitation methods For Year 9.

What is your Chemistry target grade?

What grade did you achieve in your End of Year exam?

What grade would you expect to achieve on a test on making salts before tackling this formative??

1. Measure 50cm3 of sulphuric acid with a measuring cylinder. -

   Pour the sulfuric acid into a beaker

   Warm the sulphuric acid in the beaker
2. Wash the crystals

   (using a minimum volume of cold distilled water)

   Dry the crystals using filter paper.
3. Add a spatula of copper oxide (or copper carbonate)

   Add additional copper oxide until no more reacts.
4. Concentrate the filtrate

   (evaporate some of the water using the apparatus shown in the diagram)
5. Place the concentrated solution in an crystallising dish.

   Leave in a warm dry place.
6. Filter the Copper oxide and copper sulfate mixture.

   Collect the filtrate in an evaporating dish.

Feel free to use the hint.

1. Heat the filtrate in an evaporating dish (over a water bath)
2. Add iron to excess then filter the excess iron from the iron sulfate
3. Wash the crystals with distilled water dry the crystals with filter paper
4. leave the concentrated filtrate in a warm place to evaporate the water.

Which acid is used to prepare iron sulphate?

(hint there is only one correct answer)

How is the excess iron is removed from the solution of iron sulphate?

Anhydrous iron chloride is made by direct combination of elements. Which elements are used?

Feel free to use the hint.

1. Zinc added to dilute sulphuric acid until no more zinc reacts (Note bubbles of hydrogen given off)
2. Excess zinc is removed by filtration to produce a filtrate of zinc sulfate.
3. Solution is heated to remove some water so zinc sulfate crystals form
4. Zinc sulfate crystals are washed with distilled water

   The zinc sulfate crystals are dried between two pieces of filter paper.

Making insoluble salts What will the student see when the sodium sulfate and lead nitrate solutions are mixed and react?

Making insoluble salts The student can separate and collect the insoluble lead salt by . . . . .

Making insoluble salts What is the insoluble lead salt produced in this reaction between sodium sulfate and lead nitrate?

Making insoluble salts What is the soluble product in the reaction between sodium sulfate and lead nitrate?

There are several general methods of making salts.

Magnesium sulfate (which is soluble in water) could be made by

Mg(s) + H₂SO₄(aq) → MgSO₄(aq) + H₂(g).

MgO(s) + H₂SO₄(aq) → MgSO₄(aq) + H₂O(l)

Mg(OH)₂(s) + H₂SO₄(aq) → MgSO₄(aq) + 2H₂O(l)

MgCO₃(s) + H₂SO₄(aq) → MgSO₄(aq) + H₂O(l) +CO₂(g)

Hint Mg(OH)2 is insoluble

Lead sulphate, an insoluble salt, can only be prepared by reacting two soluble salts to make a precipitate of an insoluble salt.

Which solution would react with lead nitrate solution to produce lead sulphate?

Reactions of metals + acids (Note that only the metals above hydrogen in the reactivity series will react with acids)

What grade would you expect to achieve on a test on making salts after completing this formative??