1. HCl (H:1, Cl 35.5) ---> 1+35.5 = 36.5
2. FeS (Fe:56, S:32) ---> 56+32 = 88
3. Cl2 (Cl:35.5) ---> 35.5 x 2 = 71
4. CaC03 (Ca:40, C: 12, O: 16) ---> 40 + 12 + 3(16) = 100
5. Fe0 (Fe: 56, O: 16) ---> 56+16=72
Blue, white, yellow, orange, red
D. 6 protons and 7 neutrons
As proton remains constant
The double replacement reaction
<h3>Further explanation</h3>
Given
Reaction if Na₂S + HCl
Required
Type of reaction
Solution
The double replacement reaction occurs when there is a displacement of the cations and anions of the reactants involved in the reaction to form two new compounds.
The general formula for this reaction :
AB + CD ⇒ AD + CB
At the bottom of the reaction, it is shown the number of atoms of each compound in the reactants and products which indicates the application of <em>the law of conservation of mass</em>, that the number of atoms in the reactants will be the same as the number of atoms in the product, so the reaction is said to be in a balanced state.
