Group 1 - Alkali metals

Question 1

What are the physical properties of the alkali metals?

Answer 1

1) They are soft
2) They have relatively low melting points - going down group 1, the melting points decrease
3) They have low densities (can float on water)

Question 2

Why do all Group 1 elements have similar chemical properties?

Answer 2

All elements in Group 1 have one electron in their outermost energy shell/the same number of electrons in their outer energy shell

Question 3

What are the products when alkali metals react with water?

Answer 3

A metal hydroxide and hydrogen

Question 4

What is a base?

Answer 4

A substance that reacts with an acid to neutralise it and produce a salt

Question 5

What are properties of an alkaline solution?

Answer 5

The pH value is higher than 7 and the universal indicator turns blue/purple

Question 6

What are the observations when lithium reacts with water?

Answer 6

Fizzes, slowly becomes smaller until it disappears

Question 7

What are the observations when sodium reacts with water?

Answer 7

Melts to form a ball, fizzes, quickly becomes smaller until it disappears

Question 8

What are the observations when potassium reacts with water?

Answer 8

Quickly melts to form a ball, burns violently with a lilac flame, disappears rapidly with a small explosion

Question 9

Why does the reactivity of Group 1 elements increase as you go down the group?

Answer 9

1) The atoms become larger
2) The outer energy shell containing one electron moves further away from the nucleus
3) The force of attraction decreases between the electron and the nucleus
4) The outer electron is lost more easily