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(5c) (i) - P is Ca^2a+,Calcium ion Q is magnesium ion Ca^(2a+)+H2(^+) + O2(^2-)->Ca(OH)2
(ii) To the unknown substance in the container, add copper(II)tetraoxosulphate(IV)solution, If a blue precipitate is formed. This confirms the presence of water.

(iii)
-Furring of kettle and boiler
-Stalagmite and Stalactite
(iv) Na2SO4 + Ca(OH)2->CaSO4 + NaOH

(5b) (i) -Solubility is the amount of solute of moles in which can dissolve in 1dm^3 of solvent at standard temperature and pressure
-Sateurated solution is the solution in which contains more solute than it can dissolve at a particular temperature
(ii) -Temperature -Surface area of solid
(iii) Given; mass of Z=10.2g Volume(V)=15.4cm^3 Temperature=40degreesC Molar mass of Z=331 Mole=10.2g/331gmol Solubility=Mole/Volume =0.031/(15.4*1000) =2*10^-6mol/dm^3

(5a) (i)-hydrogen chloride
(ii)-They are soluble in water
(iii)-They are less dense than air

(1a) Esterification is the reaction between organic acid e.g ethanoic acid and organic base e.g ethanol to produce salt e.g alkanoate and water

(1b) -Low melting point
-Low thermal capacity

(1b) Duralumin cosist of aluminium,magnesium amd manganese

(1d) -Raw materials is the chemical or physical materials in its natural or uncombined form
-Primary product is the useful product during chemical reactions

(1e) Charles law states the volume of a fixed ma$$ of a gas is directly proportional to the temperature provided pressure remains constant

(1f) -Eye shades
-Laaboratory coats
-Hand gloves -Spatula

(1g)
-Ammonia is used as a refrigerant in refrigerators
-Ammonia is used in production of amine and amide

(1h) -Cracking -Sodium Ethanoate
– (1i) H2S04=0 (1*2)+S+(-2)4=0 2+S-8=0 S-6=0 S=6

(1j) -Sodium trioxochlorate(v)
-Copper (ii)tetraoxosulphate pentahydrate

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Posted by Dickson on April 20, 2015.

Categories: Education