1.1 ATOMIC STRUCTURE TEST MARK SCHEME

1. (a)

Relative mass
Relative charge

Proton
1
+1
(1)
Electron
0 (or )
–1
(1)
Neutron
1
0
(1)
3
(b) (Number of) protons or and + (number of) neutrons (1) CE mass of p
(number of) protons (1)
Allow no. of nucleons / amount of p & n. ignore additional comment about electrons but penalise ‘+ electrons’ 2
(c) B (1)
(1)
(allow Boron in words) penalise 9.0

(d) In common number of protons (or electrons) (1)
Difference number of neutrons (1) 2

(e) × 12 (1) molecule, element, entity } instead of atom loses 1st mark or × 12 (1) or mean mass of an atom {compared with, relative to {an atom of 12C taken as 12, of a 12C atom 2 (f) (i)
(treat one wrong multiplicand as AE –1, 2 mistakes CE)
= 84×1 (1)
(ignore units)
(iv) Kr (1)
(allow conseq) 4
[15]

2. (a) same M/Z (1) 1 (b) not accelerated (1) 1 (c) RMM = 58 (1) because this is the peak with the largest m/z ratio (1) or 58 is the molecular/parent ion peak 2
[4]

3. (a) 2 (b) 1s2 2s2 (1) 1

(c) 1 (d) (i) Cu 3d10 4s1 / 4s1 3d10 ) (1) ) mark independently (ii) Cu2+ 3d9 ) (1) 2
[6]

4. (a) First ionisation energy equation Li(g) ® Li+(g) + e– (1) Second ionisation energy equation Li+(g) ® Li2+(g) e– (1) tate symbols (1) 3
(b) (i) He’s electron in 1s (1) closer to nucleus (or no shielding) (1)
(or converse argument for Li)
(ii) Be’s outer electron in 2s (1) lower in energy than 2p (1)

(iii) more protons (1) or increased nuclear charge attracting electrons in the same {shell/orbital/sub–shell/energy level (1) or similar shielding
(iv) Electron removed from positive ion (1) which attracts the