14 I REACTIVITY SERIES

Question 1

Colors of
group ( I ) metal &
metal oxide?

Answer 1

grey
white

Question 2

Oxidation in term of
- oxygen
- hydrogen
- electrons

Answer 2

• gain of oxygen
• loss of hydrogen
• loss of electrons

Question 3

Reduction in term of
- oxygen
- hydrogen
- electrons

Answer 3

• loss of oxygen
• gain of hydrogen
• gain of electrons

Question 4

What is meant by oxidising agent?
( in term of oxygen)

Answer 4

• oxidises something else by giving away its oxygen, oxidising it
• oxidising agent always gets reduced

Question 5

What is meant by reducing agent?
( in term of oxygen)

Answer 5

• it takes the oxygen away from something else, reducing it
• therefore reducing agent gains oxygen itself and always gets oxidised

Question 6

What is meant by oxidising agent?
( in term of electrons)

Answer 6

• accept electrons and therefore reduced in the reaction
• oxidises something else by taking electrons away from it

Question 7

What is meant by oxidising agent?
( in term of electrons)

Answer 7

• give away electrons and therefore oxidised in the reaction
• reduces something else by giving electrons to it

Question 8

Explain why the Aluminium hardly reacts at all with dilute acid in the cold, but reacts vigorously after even gently heating?

Answer 8

Aluminium is covered by a very thin, but very strong layer of aluminium oxide, which prevents the acid getting at the aluminium underneath.
On heating, the acid removes the layer, and the aluminium can show its true reactivity, and produces a vigorous reaction

Question 9

Describe and explain the effect that galvanised steel has.

Answer 9

The zinc prevents iron rusting even when the coating is scratched. Zinc is more reactive than iron and so corrodes ( reacts with oxygen/water ) instead of iron.