Chemistry- reactivity series

Topic-2d

What are the products when a reactive metal reacts with cold water?

A metal hydroxide (alkaline solution) and hydrogen gas.

E.g.: 2K + 2H₂O → 2KOH + H₂↑

What are the products when a metal reacts with dilute hydrochloric or sulfuric acid?

A salt and hydrogen gas.

E.g.: metal + acid → salt + H₂↑

What can you observe when a metal reacts with water or acid?

Bubbles of hydrogen gas are given off.

Which metal is extremely unreactive and does not react with water, acids, or oxygen?

Gold

How can you determine relative reactivity of metals?

By observing if they react with water (very reactive), acid (reactive), or only with oxygen (less reactive)

What is a displacement reaction between metals and metal oxides or metal salt solutions?

A more reactive metal displaces a less reactive metal from its compound.

What happens in a displacement reaction with metal salts?

More reactive metal dissolves, less reactive metal coats the surface or forms crystals.

What is the reactivity series of common metals (and non-metals included)?

1. Potassium

2. Sodium

3. Lithium

4. Calcium

5. Magnesium

6. Aluminium

7. Carbon

8. Zinc

9. Iron

10. Hydrogen

11. Copper

12. Silver

13. Gold

How does the reactivity of a metal relate to ion formation?

The more reactive the metal, the more easily it forms positive ions.

What conditions are necessary for iron to rust?

Both air (oxygen) and water.

What type of reaction is rusting?

Oxidation — iron gains oxygen to form iron oxide.

How can rusting be prevented using barrier methods?

By coating the metal with:

• Paint

• Plastic

• Oil or grease

• Desiccant (to remove water vapour)

• Vacuum-sealed container (removes oxygen)

What is sacrificial protection?

Coating iron with a more reactive metal (e.g. zinc) that corrodes instead, protecting the iron underneath

What is galvanising?

A method of rust prevention where iron is coated with zinc for sacrificial protection.