Question

The chemical equation given below represents the chemical reaction between lithium (Li) and sulfur (S). In the equation, why is the number 2 present in front of lithium on the reactants side of the equation?
A. to show the number of lithium atoms involved in the reaction
B. to show the number of electrons gained by lithium in the reaction
C. to show the atomic number of lithium in the periodic table
D. to show the number of electrons lost by lithium in the reaction

Answer 1

Answer:

A. to show the number of lithium atoms involved in the reaction

Explanation:

The reaction between lithium and sulfur produces lithium sulfide where two lithium and one sulfur atoms react.

Balanced equation: 2 Li + S = Li2S

The 2 present before Li on the reactant's side shows how many lithium atoms are supposed to be present per every 1 sulfur atom for this reaction to be balanced and true.

That is it! :)

Answer 2

Answer: Option (A) is the correct answer.

Explanation:

The given chemical reaction equation is as follows.

         $2Li + S \rightarrow Li_{2}S$

As the number of atoms on both reactant and product side are the same. Hence, it is a balanced chemical reaction equation.

Here, number 2 before lithium atom represents that two atoms of lithium are taking part in the reaction. As there is no coefficient or number placed before the sulfur atom this means that only one atom of sulfur is reacting in the reaction.

Thus, we can conclude that the number 2 present in front of lithium on the reactants side of the equation shows the number of lithium atoms involved in the reaction.