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s alt solubility rules. 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
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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 precipitatewhich 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 experiment Name the precipitates and write word and balanced equations
exercise • For each of the salts below: • Decide on the method you will use • Select appropriate reagents • Salts: • potassium chloride • copper nitrate • lead sulphate • magnesium chloride • ammonium nitrate • calcium sulphate