2:17 know the order of reactivity of these metals: potassium, sodium, lithium, calcium, magnesium, aluminium, zinc, iron, copper, silver, gold

A more reactive metal will displace a less reactive metal.

In addition a more reactive metal will react more vigorously than a less reactive metal.

For example, potassium takes a shorter time to react than sodium:

Past paper questions on spec point:

Spec	Q'stion	Ans	MS
2:17	Jan '14 (1), Q 11 b	Answer	MkS
2:17	Jan '16 (1), Q 9 f i	Answer	MkS
2:17	Jan '18 (1), Q 8 b ii	Answer	MkS
2:17	Jan '18 (1), Q 8 b iii	Answer	MkS
2:17	May '12 (1), Q 2 a iii	Answer	MkS
2:17	May '15 (1R), Q 12 c	Answer	MkS
2:17	May '15 (1R), Q 4 a	Answer	MkS
2:17	May '15 (2), Q 6 a	Answer	MkS
2:17	May '16 (1), Q 12 c ii	Answer	MkS
2:17	May '16 (1), Q 5 b ii	Answer	MkS
2:17	May '16 (1), Q 7 b	Answer	MkS
2:17	May '17 (1), Q 3 b iii	Answer	MkS
2:17	May '17 (1R), Q 6 c i	Answer	MkS
2:17	May '17 (1R), Q 7 a i	Answer	MkS
2:17	May '17 (1R), Q 7 a ii	Answer	MkS
2:17	May '17 (1R), Q 9 a iii	Answer	MkS