Question

Write the formulae of the salts given below.
Potassium sulphate, Sodium sulphate, Calcium sulphate, Magnesium sulphate, Copper Sulphate, Sodium chloride, Sodium nitrate, Sodium carbonate and Ammonium chloride

Answer 1

Hint: We write the metal ion first in the chemical formula of the salt. We need to write the number of the cations or anions in a way that the salt does not have charge and becomes neutral.

Complete step by step solution:
In the formula of the salts, the chemical symbol of metal is written first followed by the anion. We will write the formula of the salts one by one but before that let’s have a look at the formula of the anions.
- Anions are the negatively charged ions present in the salt.
- Sulphate is an anion with chemical formula $S{O_4}^{2 - }$. It has a charge of -2.
- Nitrate is an anion with chemical formula $N{O_3}^ - $. The overall charge on nitrate anion is -1.
- Chloride is a monatomic anion with formula $C{l^ - }$. We can see that the charge is -1.
- Carbonate is an anion with charge -2 and formula is $C{O_3}^{2 - }$.
1) Potassium sulphate:
The chemical formula for sulphate is $S{O_4}^{2 - }$ and potassium has a chemical symbol of K. So, its chemical formula is ${K_2}S{O_4}$. Here, we write two atoms of potassium because that will balance the charge of sulphate ions as potassium ions have charge of +1.
2) Sodium sulphate:
Sulphate can be shown by $S{O_4}^{2 - }$ and sodium has a chemical symbol of Na. So, its chemical formula is $N{a_2}S{O_4}$.
3) Calcium sulphate:
The chemical symbol of Calcium is Ca and it has a charge of +2. So, the chemical formula of Calcium sulphate is $CaS{O_4}$.
4) Magnesium Sulphate:
The chemical symbol of magnesium is Mg and it also has a charge of +2. So, the chemical formula of magnesium sulphate is $MgS{O_4}$.
5) Copper sulphate:
Cu is the chemical symbol of copper which has a charge of +2. So, its chemical formula is $CuS{O_4}$.
6) Sodium chloride:
It has one Na ion and one Cl ion. So, the chemical formula is NaCl.
7) Sodium nitrate:
It has one Na ion and one nitrate ion. So, its chemical formula is $NaN{O_3}$.
8) Sodium carbonate:
It has two Na ions and one chloride ion. So, its chemical formula is $N{a_2}C{O_3}$.
9) Ammonium chloride:
Ammonium ion can be shown as $N{H_4}^ + $. So, its chemical formula will be $N{H_4}Cl$.

Note: Do not get confused between nitrate and nitrite, the chemical formula of them are $N{O_3}^ - $ and $N{O_2}^ - $ respectively. If salt has the word ‘copper’ or ‘cupric’ then the Cu is in +2 state and if ‘cuprous’ word is used, then it shows that copper is in +1 state.