1
Atomic structure
●● TEST YOURSELF ON PRIOR KNOWLEDGE 1
1 number of protons in the nucleus of an atom
2 a)
+1, 1
b) −1,
c)
3 a)
0, 1
1
1840
atoms with the same number of protons but a different number
of neutrons
b) 17 protons; 17 electrons and 20 neutrons
4 a)
2, 8, 5
b) 2, 1
c)
2, 6
d) 2, 8, 8, 1
e)
2, 8, 8
f)
2
g)
2, 8, 3
5 phosphorus or 31
15P
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1 a)
19 protons;
b) 9 protons;
c)
19 electrons;
9 electrons;
20 neutrons
10 neutrons
56 protons;
56 electrons;
81 neutrons
d) 88 protons;
88 electrons;
138 neutrons
2 a)
Isotope
81
35Br
b) 79.99
3 a)
69.2%
b) 63.62
atomic number
mass number
% abundance
35
79
50.5
1
4 107.96
5 7.1
6
10B
is 20%; 11B is 80%
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1 20.2; neon
2 207
3 a)
58
b) 43
c)
i)
58
ii) C4H10
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1 i)
1s2
ii) 1s2 2s2 2p6 3s2 3p6
iii) 1s2 2s2 2p6
iv) 1s2 2s2 2p6
v)
1s2 2s2 2p6 3s2 3p6 3d6
vi) 1s2 2s2 2p6 3s2 3p6 3d5
vii) 1s2 2s2 2p6 3s2 3p6 3d8
1
Atomic structure
viii) 1s2 2s2 2p6 3s2 3p6 3d9
ix) 1s2 2s2 2p6 3s2 3p6 3d3
x)
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6
2 B
3 i)
B
ii) A
iii) C
iv) C
v)
2
A
vi) D
vii) D
viii) D
ix) B
x)
B
xi) A
xii) D
1 The first ionisation energy is the energy required to remove one mole of
electrons from one mole of gaseous atoms to form one mole of gaseous
1+ ions.
2 kJ mol−1
3 a)
Si(g) → Si+(g) + e−
TEST YOURSELF 5
●● TEST YOURSELF 5
b) K+(g) → K2+(g) + e−
c)
C2+(g) → C3+(g) + e−
4 M2O3
3