Page 167 - Chemistry

 Distilled water
 100ml measuring cylinder
 One filter funnel
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 One 25cm pipette
 A clamp and stand
 Aphenolphalein indicator
 3 conical flasks
 White tile
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 Solution F: about 30cm of 1.0M sodium hydroxide solution
 A 10ml measuring cylinder
 A 100ml plastic beaker
 Means of labeLling
o
 A 110 C thermometer
 Solid D, 0.5g Zinc Sulphate crystals
 Metallic spatula
 1 boiling tube
 5 clean dry test tubes
 Test tube holder
 Bench solutions supplied with droppers
 Dilute nitric acid solution, 2
 2M sodium hydroxide solution
 2M aqueous ammonia solution
 0.5M Barium nitrate solution
 0.5M Lead (ii) Nitrate solution
NOTES
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(a) (i) Solution P is prepared by dissolving 17.2cm of concentrated hydrochloric acid in
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about 250cm of distilled water and adding water to make 1litre of solution
(ii) Solution Q is prepared by dissolving 64g of sodium hydroxide pellets in about 250cm 3

of distilled water and making it to 1litre of solution
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(iii) Solution R is prepared by dissolving 13.75cm of concentrated sulphuric acid in about
250cm of distilled water and making it to 1litre of solution

(b) Solid D is 0.5g of Zinc Sulphate crystals
1. You are provided with:
- Solution P, 0.2 M hydrochloric acid
- Solution Q, sodium hydroxide solution
- Solution R, containing 49g/Litre of a dibasic acid, H 2A
You are required to:
Dilute solution Q with distilled water
Standardize the diluted solution Q with solution P
Determine the relative formula mass of A

Procedure 1:
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Pipette 25cm of Q into a clean dry 250ml volumetric flask. Measure 175cm of distilled water
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using a 100cm measuring cylinder and add it to solution Q in the flask. Shake well. Label
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this as solution S and keep it for further tests in procedure I and II. Pipette 25cm of solution S
into a clean dry conical flask. Add 2 to 3drops of Phenolphthalein indicator and titrate with
solution P. record your results in the table I below. Repeat the procedure to obtain accurate
results.
Table I
Titration number I 2 3
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