Group 1 (alkali metals)

Question 1

understand how the similarities in the reactions of lithium, sodium and potassium with water provide evidence for their recognition as a family of elements

Answer 1

Group 1 metals such as potassium, sodium and lithium, react with water to produce a metal hydroxide and hydrogen

fizzing (hydrogen is produced), metal floats and moves around on the water, metal disappears

Question 2

The observations for the reaction of lithium and water are:

Answer 2

fizzing (hydrogen gas is released)
lithium floats and moves around on the water
lithium disappears

Question 3

The reaction of sodium and water is more vigorous than lithium’s:

Answer 3

fizzing (hydrogen gas is released)
sodium floats and moves around on the water
sodium melts into a silver-coloured ball
sodium disappears

Question 4

The reaction of potassium and water is more vigorous than sodium’s:

Answer 4

fizzing (hydrogen gas is released)
potassium floats and moves around on the water
catches fire with a LILAC flame
potassium disappears