Page 38 - Big Ideas Year 10 sciPAD 2025

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38 SCIPAD - BIG IDEAS - BOOK 2
BASIS OF CHEMICAL REACTIONS
Writing Chemical Equations - Acid + Base
In a previous practical you added an acid to a base to make a neutral solution. During this
reaction a salt was formed. In chemistry, the word ‘salt’ refers to more than the white crystals
you put on fish and chips. That particular salt is called sodium chloride (NaCl), but there are many
other salts.
A salt is the name of a compound formed by a metal and a non-metal. Sodium chloride, for
example, is made of sodium ions (metal) and chloride ions (non-metal).
A salt is always made when an acid is neutralised by a base. But the exact salt made depends
upon which acid and base were used. The general equation for many neutralisation reactions is:
Acid + base salt + water
The name of a salt is composed of two parts:
Sodium chloride The second part comes from
the acid that was used.
The first part is from the metal
in the base that was used.
The diagram below shows how a full chemical equation would look.
Hydrochloric acid + sodium hydroxide sodium chloride + water
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There are three common laboratory acids, so figuring out the second part of any salt produced
by these acids is easier if you learn the following table.
Acid Salt produced
Hydrochloric acid Chlorides
Sulfuric acid Sulfates
Nitric acid Nitrates
1. Complete the following equations by writing in the name of the salt produced.
(a) Nitric acid + sodium hydroxide
(b) Nitric acid + magnesium hydroxide 
(c) Sulfuric acid + iron hydroxide 
(d) Sulfuric acid + zinc hydroxide 
(e) Hydrochloric acid + sodium hydroxide 
(f) Hydrochloric acid + lead hydroxide 
(g) Sulfuric acid + calcium hydroxide 
(h) Nitric acid + nickel hydroxide 
(i) Hydrochloric acid + copper hydroxide 
(j) Sulfuric acid + potassium hydroxide 
(k) Nitric acid + beryllium hydroxide
Sodium nitrate
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