5 This question is about groups in the periodic table.
The elements in Group 1 become more reactive going down the group. Rubidium is below potassium in Group 1.
Rubidium and potassium are added to water.
5-1 Predict one observation you would see that shows that rubidium is more reactive than potassium
[1 mark]
ANSWER
More vigorous bubbling for rubidium as compared to potassium;
Bigger /brighter flame for Rubidiumas compared to potassium.
5-2 Explain why rubidium is more reactive than potassium.
[3 marks]
ANSWER
Rubidium’s outer shell valence electron is further from the nucleus so there is less (electrostatic) attraction between the nucleus and the outer electron in rubidium hence the valence electron in rubidium is more easily lost and making it more reactive.
5-3 Complete the equation for the reaction of rubidium with water.
You should balance the equation.
[3 marks]
ANSWER
2Rb + 2H2O → 2RbOH + H2
The noble gases are in Group 0.
5-4 Which is a correct statement about the noble gases?
ANSWER
The noble gases have boiling points that increase going down the group.
5-5 Table 1 shows information about the three isotopes of neon.
Table 1
Calculate the relative atomic mass (Ar) of neon. Give your answer to 3 significant figures.
[3 marks]
ANSWER
