salt solubility rulessoluble insolubleall nitrates

all chlorides except….

all sulphates except…..

sodium and potassium carbonates

all sodium, potassium and ammonium salts

….silver chloride, lead chloride

….barium sulphate, lead sulphate, calcium sulphate

….all other carbonates

titration• add acid via burette to alkali`+ indicator until neutral (or

until temperature stops rising)• measure volume of acid added; throw away • solution as it contains the indicator;• add same volume of acid to same amount of • alkali without indicator• obtain dry salt from solution (see later slide)

titration animation

excess base• warm acid • add excess base to acid until no more

dissolves (warm acid if necessary)• filter off excess base• obtain salt from (see next slide)

excess base animation

obtaining dry salt from solution

• Concentrate solution until it becomes saturated which is done by driving off most of the water by heating it. Solution is saturated when crystals form on a glass rod dipped in the solution.

• Stop heating and allow solution to cool and salt crystals to form.

• Filter the crystals to remove water• Wash crystals with a little water• Dry crystals with filter paper or place on warm

gauze.

precipitation• make 2 solutions each one containing 1 ion of the

salt to be made (use soluble salts!!!)• add the two solutions• filter off the precipitate which is the insoluble salt• wash the residue in the filter paper with distilled

water• dry with other filter paper or place on warm gauze

precipitation salts experimentcopper

sulfate (aq)lead nitrate

(aq)potassium iodide (aq)

silver nitrate (aq)

sodium carbonate

(aq)copper sulfate (aq)

white ppte brown ppte light blue ppte

blue ppte

lead nitrate (aq)

yellow ppte - white ppte

potassium iodide (aq)

yellow ppte -

silver nitrate (aq)

yellow ppte

sodium carbonate (aq)

Name the precipitates and write word and balanced equations

exercise• For each of the salts below:

o Decide on the method you will useo Select appropriate reagents

• Salts:1. potassium chloride2. copper nitrate3. lead sulphate4. magnesium chloride5. ammonium nitrate6. calcium sulphate