1. Metals, especially when
, react with the oxygen in air to form a metal
.

2. Complete the following ...
(a)
+ oxygen ==> sodium oxide
(b) copper +
==> copper oxide
(c) zinc + oxygen ==>
oxide

3a. When copper is heated in air, a
layer of
slowly forms.
3b. When magnesium is heated in air it burns with a bright flame to form a
powder of
.
3c. These observations tell you that magnesium is
reactive, so
in the reactivity series than copper.

3d. If gold is heated in air, there is hardly any reaction, and this tells you that gold is
reactive, and so
in the reactivity series than copper.

4. These reactions can be represented by symbol equations. Complete ...
(a) 2
+ O
2 ==>
MgO
(b)
Fe +
O
2 ==> Fe
3O
4