CIE IGCSE Chemistry Solved Past Paper May/June 2019 P41
bi) 12 12 1 2
12 14 12
ii) Isotopes
iii) Because they have the same number of electrons in their outer shells
c) Beryllium metal and chloride ion
d) 2,8,3
2a) 80?
c) Because energy is needed to break the bonds between molecules
d) Vibration increased
e) Melting point decreases and boiling point increases
3a) Zinc blend is roasted in hot air to produce zinc oxide and then it is
reduced by coke.Zinc is then collected in a condensing tray by
distillation
b) Brass
c) They form colorful compounds and also act as catalyst
di) Anhydrous copper(ll)sulfate
ii) From white to blue
ei) 4KI + 2CuSO42CuI + I2 + 2K2SO4
ii) 1+
iii) It gains electrons
(iv) Iodide ion
4 ai) Proton donor
ii) CH3COO- + H+
bi) Solid dissolves faster and fizzing stops earlier
ii) Temperature, concentration of acid, and surface area of lumps
c) 50/1000*2=0.1 mol
(0.1)/2=0.05 mol
24+12+(16*3)=84=Mr
Mass = 84*0.05 = 4.2g
di) To make sure all of magnesium chloride goes through and none is left
behind
ii) To remove any remaining acid
iii) Heat to the point of crystallisation point then let it cool, filter was and
dry it
ei) It is the solid formed when two solutions are mixed together
ii) Silver nitrate
5a) CnH2n
b) C5H10
C) E because it has the longest carbon chain
d) A, because it has the lowest Mr
e) Changes from brown to colourless
1,2-dibromobutane
fii) Steam, 60 atmospheres of pressure along with phosphoric acid acting
as a catalyst
gi) Addition polymerisation
ii) Poly(but-1-ene)
iv) CH2