Step-by-step explanation:
sodium (Na +)
Carbonate ion (CO₃²⁻)
Ionic compounds are formed between ions (Anions and Cations).
For a neutral compound to be formed, the charges of the ions must cancel each other out.
Sodium ion has a charge of +1
Carbonate ion has a charge of -2
The only way to make sure both ions have similar charges is to multiply each ion by the coefficient of the other.
Thus we have;
Sodium ion = +1 * 2 = +2
Carbonate ion = -2 * 1 = -2
From this, the chemical formular of the product formed between both ions must contain 2 sodium ions and one carbonate ion.
This is given by;
Na₂CO3