Air, combustion, rusting and fire fighting questions | form one Chemistry

Define the following terminologies;

a)rust

b)rusting

c)mention the three necessary conditions for iron/steel to rust

1)i. What is air?

  ii) mention composition of the following gases in the atmosphere;

    a)0xygen    b) Carbondioxide  c) nitrogen  and  d) Argon

iii) is air a mixture or compound? explain briefly.

1)Define the followings;

   i. Firefighting

   ii.flame

   iii.mention the necessary conditions needed to start a fire.

   iv) does oxygen burn or supports combustion?

Give four properties of hydrogen.

When a burning splint is introduced into a gas jar containing carbon dioxide, the flame goes out.
(i) What two properties of carbon dioxide does this experiment illustrate?
(ii) What type of equipment used widely in everyday life makes use of these two properties?

1. i)State two conditions required for iron to rust

          ii)List two methods which are used to prevent rusting of iron.

2. State three properties that make aluminium useful in overhead cables.

Why oxygen as one of the components of air is unique?
A It support combustion
B It is a diatomic gas.
C It forms the largest part of the air.
D It has the largest density.

Which conditions are necessary for iron nails to rust?
A oxygen and moisture
B carbon and oxygen
C carbon dioxide and oxygen
D oxygen and nitrogen.

Giving a reason, state whether rust will form or not in each of the situations (i) - (vi).

1. Iron bar is dipped into boiling water.
2. Painted iron is dipped into un-boiled water.
3. Iron bar is dipped in un-boiled water.
4. Oiled bar is left outside the room over nights.
5. Aluminium wire is dipped in un-boiled water.
6. A dry iron bar is wrapped with cotton wool.

Briefly explain any four methods of preventing rusting.