Question

question 1
the 2 in the formula mgcl₂ is a
(image of lewis structure: :cl:mg:cl: with electron dots)
○ reactant
○ subscript
○ coefficient
○ product
question 2

Explanation:

A subscript in a chemical formula is a small number written below and to the right of an element symbol, indicating the number of atoms of that element in a compound. In $\text{MgCl}_2$, the 2 is written after Cl, showing there are 2 chlorine atoms per magnesium atom in the compound. Reactants and products are substances in chemical reactions, while coefficients are numbers in front of formulas indicating the number of molecules/units, which does not match the role of this 2.

Answer:

B. Subscript