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
By looking at the reaction, we can see that the reactants must absorb 315kJ of energy in order to form the reactants. This means that the reaction is absorbing energy, which would make it A. endothermic.
Hope this helps!
