Reactions of metals with acids

 

Metals and acids

Some metals and acids react to make a salt and hydrogen gas.

 

Metal + Acid → Salt + Hydrogen

 

You can use the acronym M.A.S.H. to remember this general reaction.

The metal gets smaller and smaller as it reacts with the acid.

You can see bubbles of gas coming out of the solution. The gas is hydrogen.

You can test this by using a lit splint. Hydrogen is flammable, so it will make a squeaky pop sound when it meets the flame. This proves that hydrogen is there.

 

Reactivity of metals

Some metals react very easily. They make new substances quickly when they join in chemical reactions. Other metals react very slowly, and they do not join in chemical reactions easily.

We can make a list of the metals based on how easily they react. The most reactive metals are at the top of the list, and the least reactive metals are at the bottom of the list. This list is called the reactivity series.

 

 

 

Naming the salt from the reaction of a metal and an acid

The name of the salt that is made from the reaction of a metal and an acid depends on the names of the metal and the acid.

Name of metal + name of acid → salt name

 

1. The first word is the name of the metal

 

For example, if magnesium reacts with an acid, the salt will have magnesium as its first word.

 

2. The second word of the name is taken from the name of the acid

 

Hydrochloric acid → chloride

Nitric acid → nitrate

Sulfuric acid → sulfate

 

For example, zinc reacts with hydrochloric acid to produce zinc chloride and hydrogen.

 

The reaction of metals with acids can be described using the following chemical equation:

magnesium + sulfuric acid → magnesium sulfate + hydrogen

Or (symbol equation):

Mg + H2SO2 → MgSO2 + H2

 

🧪 Knowledge Check: Metal Reactions

Test your knowledge of how metals react with acids and oxygen based on the guide.

1. Complete the general word equation: Metal + Acid → _______ + Hydrogen.

• Oxygen
• Salt
• Water

2. What is the name of the test used to identify hydrogen gas?

• The glowing splint test
• The limewater test
• The squeaky pop test

3. Which substance is produced when magnesium burns in oxygen?

• Magnesium oxide
• Magnesium chloride
• Magnesium sulphate

4. What type of reaction occurs when a metal gains oxygen?

• Neutralisation
• Oxidation
• Evaporation

5. When iron reacts with dilute sulphuric acid, which salt is formed?

• Iron chloride
• Iron oxide
• Iron sulphate

Click to Reveal Answers

1. Salt (Metals and acids always produce a salt and hydrogen).
2. The squeaky pop test (Hydrogen ignites with a characteristic sound).
3. Magnesium oxide (The product of magnesium reacting with oxygen).
4. Oxidation (Adding oxygen to a substance is called oxidation).
5. Iron sulphate (Sulphuric acid produces sulphate salts).

 

Summary:

 

• Most metals react with acids.
• A salt and hydrogen are formed when a metal and an acid react.
• This is the general word equation for this reaction: acid + metal → hydrogen + salt.