Unit 1
Exercises
1A
(i)3.45 10 –^5 (ii) 3 108
(iii)8.205 75 10 –^2 (iv)3.5 100
(v)6.022 1023 (vi)1.7 101
1B
(i)379.75 (or 380) (ii)17.34 (iii)1.921 (or 1.92)
(iv)2.75 10 –^5 (v)0.409
(vi)5.517 10 –^3 (or 5.5 10 –^3 )
(vii)5.52 10 –^6
1C
(i)0.040 nm (ii)10 g (iii) 6 10 –^7 m.
1D q
(i)Rearranging,CmT. The units of Care
J
gKJg– (^1) K– (^1).
m g
(ii)Mnand the units aremolg mol–^1.
1E
Some of the alcohol in the wine has been oxidized.
1F
(i)(a) 1, (b) 4, (c) 2 or 3 (compare the example of 150 in
Box 1.3), (d) 3.
(ii)No, to four significant figures the atomic mass is
15.99 atomic mass units.
(iii)(a) 0.0347, (b) 0.035, (c) 0.03.
1G
(i)[H+(aq)]1.484 10 –^5 mol dm–^3 , which becomes
1.5 10 –^5 mol dm–^3 (two significant figures).
(ii)10.432 mg 10.4 mg to one decimal place.
(iii)pKalogKalog(8.4 10 –4mol)3.08
Revision questions
1.1Cr^3 +6.9 10 –^11 m, F–1.36 10 –^8 m,
O 1.40 10 –^8 m.
1.2Uncertainty is at least 0.1 °C.
1.3 (i)0.1235 V, (ii)12.45 m, (iii)0.003 558,
(iv)1201 K.
1.4 (i)3.29 10 –^4 , (ii)0.449.
1.5Total mass is 0.49 g (to two decimal places).
1.6Units are mol^2 dm–^6 .Kw 1 10 –^14 ([H 3 O+] is
supplied to only one significant figure).
1.7 has units of mol–^1 m^2.
1.8 (i)random
(ii)systematic (too big to be explained by draughts)
(iii)systematic (pressure is falling).
1.9 (i)pHlog(8.987 10 –^6 )(5.046 38)
- 0464 (four decimal places and rounded up).
(ii)[H+(aq)] 10 –11.^344 4.528 976 10 –^12 4.53
10 –^12 mol dm–3(three significant figures and rounded
up).
Unit 2
Exercises
2A
(i)chemical (ii)physical (iii)physical
(iv)physical (v)physical.
2B
(i)physical (ii)physical (iii)chemical
(iv)chemical (v)chemical.
2C
(i)extensive (ii)intensive (iii)extensive
(iv)intensive.
2D- (i)barium (ii)silicon (iii)argon
(iv)fluorine (v)lithium (vi)mercury
(vii)tin (viii)silver (ix)boron (x)titanium. - (i)caesium (1) bromine (1)
(ii)copper (1) chlorine (2)
(iii)iron (3) oxygen (4)
(iv)carbon (1) hydrogen (4)
(v)lead (1) sulfur (1) oxygen (4)
(vi)potassium (2) chromium (2) oxygen (7)
(vii)sodium (3) phosphorus (1) oxygen (4)
(viii)manganese (1) oxygen (2)
2E
carbon, hydrogen, oxygen, phosphorus, potassium,
iodine, nitrogen, sulfur, calcium, iron, sodium, chlorine.
2F - (i)Natrium (sudais Arabic for ‘headache’; sodium
carbonate was considered a remedy)
(ii)ferrum(Latin) (iii)plumbum(Latin)
(iv)stannum(Latin) (v)kalium(Latin)
(vi)argentum(Latin) - (i)Lise Meitner worked on uranium fission and
realized that atomic fission could produce vast
quantities of energy. (ii)Glenn T Seaborg, an American
nuclear chemist and Nobel prize winner (1951) for
investigating the chemistry of heavy elements.
(iii)Niels Bohr and (iv)Ernest Rutherford made major
contributions to our understanding of atomic structure.
2G
(i)CaO (ii)H 2 S (iii)MgF 2 (iv)MgCl 2
(v)AlF 3 (vi)Al 2 O 3 (vii)HCl (viii)LiBr
(ix)MgS (x)Mg 3 N 2.
2H
(i)Cu 2 O (ii)CuO (iii)PbO 2 (iv)Cr 2 S 3
(v)MnO 2 (vi)CrF 6 (vii)Co 2 S 3 (viii)Cr 2 O 3
(ix)V 2 O 5 (x)TiF 3 (xi)NO (xii)AsCl 3
(xiii)SF 6 (xiv)N 2 (xv)S 2 Cl 2 (xvi)N 2 O 5
(xvii)O 2 F 2 (xviii)TeO 3 (xix)Cl 2 O 6
(xx)SiCl 4.
2I
(i)CuSO 4 (ii)Cu(NO 3 ) 2 (iii)NH 4 Cl
(iv)Na 3 PO 4 (v)Ca 3 (PO 4 ) 2 (vi)H 2 SO 4
(vii)HNO 3 (viii)Al(NO 3 ) 3 (ix)Li 2 CO 3
(x)(NH 4 ) 2 CO 3 (xi)Ca(OH) 2 (xii)KHCO 3
(xiii)Ca(HCO 3 ) 2 (xiv)NaHSO 4 (xv)Fe(OH) 3.
2J
(i)N 2 3H 2 2NH 3
(ii)2NaCl 2 2NaCl
(iii)4Al3O 2 2Al 2 O 3
(iv)2Al2H 3 PO 4 2AlPO 4 3H 2
(v)4NaO 2 2Na 2 O
(vi)Mg 3 N 2 6H 2 O3Mg(OH) 2 2NH 3
(vii)2Cr 2 O 3 3Si4Cr3SiO 2
(viii)CS 2 3O 2 CO 2 2SO 2
(ix)Fe 2 O 3 3CO2Fe3CO 2
(x)4FeS 2 11O 2 2Fe 2 O 3 8SO 2.
2K
(i)4KO 2 2K 2 O
(ii)2Fe3Cl 2 2FeCl 3
(iii)2Li2H 2 O2LiOHH 2
(iv)3MgN 2 Mg 3 N 2
(v)Ca(OH) 2 CO 2 CaCO 3 H 2 O
(vi)2NaOHH 2 SO 4 Na 2 SO 4 2H 2 O
(vii)2Au 2 O 3 4Au3O 2
(viii)Cu 4HNO 3 Cu(NO 3 ) 2 2NO 2 2H 2 O
2L
(i)CaCO 3 (s)CaO(s)CO 2 (g)
(ii)Pb(NO 3 ) 2 (aq)2NaI(aq)PbI 2 (s)2NaNO 3 (aq)
(iii)2Al(s)3Cl 2 (g)2AlCl 3 (s)
(iv)CH 4 (g)2O 2 (g)CO 2 (g)2H 2 O(g).
Revision questions
2.1 (i)mixture (ii)compound (iii)element
(iv)mixture (v)compound (vi)mixture
(vii)element (viii)mixture (ix)element
(x)compound.
2.2m.p. physical,
b.p. physical,
soft physical,
corrodes chemical,
conducts electricity physical,
reacts with water chemical.
2.3liquid.
2.4gas.
2.5 (i)cuprum(Latin for Cyprus, famous for its copper
mines)
(ii)stibium(Latin for ‘mark’; once used for eyebrow
pencils)
(iii)hydrargyrum(Latin).
2.6 (i)O (ii)2O (iii)2O 2 (iv)3SO 3
(v)4Ne.
2.7 (i)lithium (2), carbon (1), oxygen (3).
(ii)calcium (1), nitrogen (2), oxygen (6).
(iii)nitrogen (3), hydrogen (12), phosphorus (1), oxygen
(4).
2.8 (i)BaF 2 (ii)SnBr 2 (iii)SnCl 4
(iv)NaCH 3 CO 2 (v)Al 2 S 3 (vi)KOH
(vii)NaBrO 3 (viii)K 2 Cr 2 O 7 (ix)(NH 4 ) 3 PO 4
(x)Pb(CN) 2.
2.9As a bleach (hair, textiles, paper, straw, leather etc.)
or as a mild antiseptic.
2.102H 2 O 2 (l)2H 2 O(I)O 2 (g).
2.11 (i)KClO 4 KCl2O 2
(ii)2S 8 3AsF 5 S 16 (AsF 6 ) 2 AsF 3
(iii)Hg2NH 4 IHgI 2 H 2 2NH 3Answers to Exercises and
Revision Questions
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