Page 222 - Chemistry

= 2.36
143.5
= 0.016446moles  ½
Mole ratio Nacl: AgCl
1 :1  ½
Moles of NCl = 0.61446moles
Mass of NaCl = RFM x moles
= 58.5 x 0.016446
= 0.962091g  ½
Mass of solvent (water) = 2.63 – 0.962091
= 1.667909g  ½
1.667909g of water dissolves 0.962091g of NaCl
100g of water dissolves = 100 x 0.962091g
1.667909
= 57.68/100g of water  ½

3
33. 24000cm = 1mol
3
80cm = 80x1
2400  1  1
= 0.00333moles

34.. (i) CH 3CH = CHCH 3 – But-z-ene
(ii) CH 3C = CH 2 ; 2– methyl 1 prop-I-ene

CH 3
(iii) CH 2 = CHCH 2CH 3 – But-I-ene

35. (a) Octane
or CH 3CH 2CH 2CH 2CH 2CH 2CH 2CH 3
 ½

36. a) Existence of same molecular formula but different structural formula √1
b) i)

Nitrogen and its compounds

1. (i) 4HN 3 (g) + 5O 2 (g) 4NO (g) + 6H 2O (g)
(ii) Act as catalyst

2+
(iii) Zn(NH 3) 4

2. a) Platinum/ copper

b) Brown fumes √
Hot rod m continues to glow red
- NO formed reacts with oxygen to form NO 2 (brown flames)
- Reaction highly exothermic

3. a) Calcium hydroxide
b) Ca(OH) 2(g) + 2NH 4CL (g) ________ 2NH 3(g) + CaCL 2 + 2H 2O (L)

4. (a) It neutralizes air to prevent violent combustion reaction from occurring.
o
(b) Its inert and have very low b.pt of -196 C
*MAT

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