The weighted mean mass of an atom of an element compared to 1/12 the mass of a c-12 atom
The mass of an isotope compared to 1/12 the mass of the C-12 isotope
The mass of an atom of an element compared to C-12
The sum of the protons and neutrons in the nucleus
10. What is the trend in melting point across period 3?
It increases 1-4, then drops for G5 before before increasing again between G6 and G7
It increases 1-3; then sharply peaks for G4 before dropping again
It decreases across the group
It increases across the group
11. These are the successive ionsations of Mg. What could A be? 738 ; 1451 ; A ; 10543 ; 13630
7730
10550
2150
1500
12. What is the trend in ionisation energy down a group?
It increases up to the fourth element then decreases
It decreases (more quantum shells)
It varies (proton and repulsion effect depends on the element)
It increases (more protons)
13. Which group of elements have the highest first ionisation energy?
Group 7
Group 8
Group 5
Group 1
14. What is trend in atomic radius across a period?
It increases up to the covalent macromolecules, then decreases
It increases (larger nucleus)
It decreases (more protons)
It increases (more electrons)
15. Why are Nitrogen and Oxygen anomalies in first ionisation energy?
Oxygen should be lower than Nitrogen, however it's nuclear charge overrides the added electron replusion
Oxygen should be lower than Nitrogen however as it is a better reducing agent it cannot loose electrons as easily
Oxygen should be higher than Nitrogen, however it is lower as it has more repulsion due to the paired outer electrons in the 2Px orbital
Oxygen should be higher than Nitrogen, however it is lower due to the fact the outer electron is being taken from a p orbital rather than an s (further from the nucleus)
16. What group is this element in, if these are successive ionisation energies: 578 1817 2744 11577 14842
