Question

explain how to count the number of atoms in a molecule that has parentheses () around it?

Explanation:

In a chemical formula with parentheses, first count atoms inside parentheses. Then multiply by the subscript outside. For example, in \(Ca(OH)_2\), inside parentheses: 1 O and 1 H. Subscript 2: multiply by 2. So total O: \(1\times2 = 2\), H: \(1\times2=2\). Plus Ca (1 atom).

Answer:

First, count the atoms within the parentheses. Then, multiply the number of each atom inside the parentheses by the sub - script number outside the parentheses.