Question

The most abundant cation in seawater is the sodium ion. The evaporation of seawater gives a mixture of ionic compounds containing sodium combined with chloride, sulfate, carbonate, bicarbonate, bromide, fluoride, and tetrahydroxyborate. [tetrahydroxyborate = B(OH)₄^–]. Write the chemical formulas of all these compounds.

1. Sodium chloride

2. Sodium sulfate

3. Sodium carbonate

4. Sodium bicarbonate

5. Sodium bromide

6. Sodium fluoride

7. Sodium tetrahydroxyborate

Answer 1

We know that Sodium forms a cation of charge +1 given by.

Note that in a chemical formula of a neutral salt, the charge of cation and anion must be balanced.

Chloride ion is represented by .

Hence, the chemical formula of compound sodium chloride can be derived as

.

Hence, the chemical formula is .

Sulphate ion is a doubly negative anion with formula .

Hence,

Note that we needed 2 Na+ cation to balance the charge since each sulfate ion carries a charge of -2.

Hence, the chemical formula is .

Carbonate anion is also a doubly negative anion given by .

Hence,

Hence, the chemical formula is .

Bicarbonate anion is the single negative anion given by .

Hence,

Hence, the chemical formula is .

Bromide ion is represented by .

Hence, the chemical formula of compound sodium chloride can be derived as

.

Hence, the chemical formula is .

Fluoride ion is represented by .

Hence, the chemical formula of compound sodium chloride can be derived as

.

Hence, the chemical formula is .

Tetrahydroxyborate is a single negative anion of formula .

Hence,

Hence, the chemical formula is .