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Home > Chemistry > Acids > Reactions of acids


Reactions of acids

Reactions of acids and metals (General/Credit)


Some metals will react with acids to neutralise them and give off hydrogen gas molecules.

The general word equation for the reaction is:



Zinc + Sulphuric acid → Zinc sulphate + Hydrogen

(Zn + H2SO4 → ZnSO4 + H2)


Remember that at Credit level you will be expected to balance formula equations.

Example question

Now try the typical Standard Grade question below.


Change the word equation below into a formula equation.

magnesium + hydrochloric acid → magnesium chloride + hydrogen

Remember the formula for a metal is just its symbol.


Mg + HCl → MgCl2 + H2


Try to balance the formula equation above.


Mg + 2HCl → MgCl2 + H2



Class Clips

Take a look at the effect of pH on food.


PH indicator

Class Clips

Why is it important to know why certain substances are acidic, neutral, or alkaline? Watch to find out.

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