What is meant by the skeletal chemical Equation

Answer- A skeletal equation is an unbalanced equation. In this unbalanced equation, the number of atoms of the elements on the reactant side does not match with the number of atoms of the same element on the product side. Example- 

H₂(g) + O₂(g) -> H₂O

The equation represents chemical reactions showcasing the unbalanced nature of chemical formulae of reactants and products. The law of conservation of mass is responsible for the balancing of chemical equations. A skeletal chemical equation does not abide by the law of conservation of mass. 

The number of atoms is not equal in both the reactants and products in an unbalanced equation. These equations do not reveal the type of reactions taking place in an equation. The state of the reactants and the catalyst is unknown in a skeletal equation. 

A skeletal equation is a step to write the complete chemical equation. The relative and the balanced side of reactants and products is not revealed. For example- 

Mg + O₂ -> MgO 

In the above equation magnesium oxide is formed when magnesium reacts with oxygen. It indicates the formulas for magnesium and oxygen. It is an example of an unbalanced equation. 

Skeletal equations depict a simpler form of chemical reactions. These equations have a sign of “+” between each formula. Some skeletal equations also use phase tags. They reveal the state of the chemical formulas. 

The chemical formulas can be in the state of solid, gas, liquid or aqueous. When something is dissolved in water, it is said to be in an aqueous state. 

Below is an example of a skeletal chemical equation using phase tags- 

NaHCO₃(s) + CH₃COOH(aq) -> CO₂(g) + H₂O(l) + Na+(aq) – CH₃COO-(aq) 

In the above equation the solid state of baking soda is reacted with an aqueous state of acetic acid (vinegar). The products of the reaction are gaseous state or carbon dioxide, liquid state of water and aqueous state of dissolved sodium and acetate atoms.