REACTIONS OF METALS
1.
A number of metals are reacted with pure oxygen. The oxides formed are dissolved in water and the
solutions are tested with litmus. Write down the numbers 1.1 to 1.9 on your answer sheet and complete
the following table by writing the answers next to the numbers.
Metal
Li
Na
K
Mg
Ca
Colour of flame
white
1.2
1.4
1.6
1.8
Formula of oxide
1.1
Na2O
1.5
1.7
CaO
Colour of litmus
blue
1.3
blue
blue
1.9
2.
The following questions refer to the reaction of Li, K and Na with oxygen.
2.1
2.2
2.3
2.4
2.5
With what colour flame does sodium burn?
Write down the equation for the reaction that takes place in 2.1.
Write down the formula of potassium oxide.
What will be the colour of litmus in an aqueous solution of potassium oxide.
Arrange the alkali metals in order of increasing reactivity.
3.
The following questions refer to potassium that is reacted with water and oxygen in separate experiments.
3.1
3.2
3.3
3.4
3.5
3.6
What are your observations when a small piece of potassium is dropped into water?
Write down the equation for the reaction that occurs in 3.1.
Under what liquid is potassium stored in the laboratory?
With what colour flame does potassium burn in oxygen?
Write down the equation for the reaction that occurs in 3.4.
What will be the colour of litmus in a solution of potassium oxide?
4.
A certain metal burns in oxygen with a white light and forms an oxide that is a white powder. When the
oxide is dissolved in water, a white suspension is formed. The suspension is tested with litmus.
4.1
4.2
4.3
4.4
Identify the element.
Write down a balanced equation for the reaction that occurred during oxidation.
What is the colour of litmus in the metal oxide solution?
Comment on the degree of solubility of the oxide giving a reason for your answer.
5.
Write down balanced equations for the following reactions:
5.1
5.2
5.3
5.4
calcium burns in oxygen.
magnesium reacts with steam.
lead oxide is strongly heated.
sodium reacts with water.
6.
Carbon, when heated until red hot, will remove oxygen from copper(II) oxide and zinc oxide, but not from
magnesium oxide. Zinc will remove oxygen from copper(II) oxide. Use this information to arrange Zn, Cu
and Mg in order of increasing reactivity.
7.
The elements W, X, Y and Z are arranged in order of increasing reactivity, with Z being the most reactive.
Using ticks and crosses in the accompanying table, indicate in which cases reactions are likely to occur.
W
X
Y
Z
WA
YB
ZC
XD
8.
The following metals are arranged in order of increasing reactivity: Cu, Fe, Zn, Mg.
8.1
8.2
Will a reaction occur between Fe2+ and Cu? Give a reason for your answer.
Write down a balanced equation for the reaction that occurs between Zn and CuSO 4.