Reactions of Acids (Edexcel IGCSE Science)

Spec point — 2.37 · describe the reactions of hydrochloric acid, sulfuric acid and nitric acid with metals, bases and metal carbonates (excluding the reactions between nitric acid and metals) to form salts

Reactions of Acids

Reactions of acids with metals

• Only metals above hydrogen in the reactivity series will react with dilute acids
• The more reactive the metal then the more vigorous the reaction will be
• Metals that are placed high on the reactivity series such as potassium and sodium are very dangerous and react explosively with acids
• When acids react with metals they form a salt and hydrogen gas
• The general equation is:

metal + acid ⟶ salt + hydrogen

• Some examples of metal-acid reactions and their equations are given below:

Table of acid-metal reactions

• In general, we can summarise the reaction of a metal that forms a +2 ion as follows:

Acids-Metals Summary Table

Reaction of acids with bases

• When an acid reacts with a base, a neutralisation reaction occurs
• In all acid-base neutralisation reactions, a salt and water are produced:

acid + base ⟶ salt + water

• The identity of the salt produced depends on the acid used and the positive ions in the base
• Hydrochloric acid produces chlorides, sulfuric acid produces sulfate salts and nitric acid produces nitrates
• Metal oxides and metal hydroxides act as bases

Acids and Metals Oxides or Hydroxides Summary Table

Reactions of Acids with Metal Carbonates

• Acids will react with metal carbonates to form the corresponding metal salt, carbon dioxide and water
• These reactions are easily distinguishable from acid – metal oxide/hydroxide reactions due to the presence of effervescence caused by the carbon dioxide gas

Acids & Metal Carbonates Reactions Table

Exam Hint If in an acid-base reaction there is effervescence produced then the base must be a metal carbonate which produces carbon dioxide gas.