What is the colour of potassium in a flame test?

• A green
• B brick-red
• C lilac
• D blue

The trend in the boiling points for these elements is similar to the trend in their melting points.

Predict a value for the boiling point of lithium.

Caesium is another element in Group 1, located below rubidium.

Predict its melting point and how its reactivity compares to rubidium.

• Melting point: $............{}^{\circ }C$
• Reactivity: $............$

The elements in Group 1 have similar chemical reactions because they have the same number of

• A protons
• B electron shells
• C neutrons
• D outer electrons

A student wrote these statements about the reactions of the Group 1 elements.

• The reactivity of the elements decreases down the group.
• The elements react with water to produce an acidic solution.
• The formula of lithium chloride is $LiCl$.
• The equation for the reaction of potassium with water is $2Na+2H_{2}O\to 2NaOH+H_2$.
• The Group 1 metals are stored under oil to prevent reaction with oxygen.

Three of the statements contain one incorrect word.

Complete the table to show each incorrect word and the correct word that should be used to replace it.