1. **Problem Statement:** We want to find out how many electrons are in a charge of $3.2 \times 10^{-18}$ coulombs (C). 2. **Understanding the Concept:** Charge is quantized, meaning it comes in whole number multiples of the elementary charge $e$, which is the charge of one electron. The elementary charge is $e = 1.6 \times 10^{-19}$ C. 3. **Formula:** The total charge $Q$ is given by: $$ Q = n e $$ where $n$ is the number of electrons. 4. **Rearranging the Formula:** To find $n$, divide the total charge $Q$ by the elementary charge $e$: $$ n = \frac{Q}{e} $$ 5. **Substitute the Values:** $$ n = \frac{3.2 \times 10^{-18}}{1.6 \times 10^{-19}} $$ 6. **Calculate:** Divide the numbers: $$ \frac{3.2}{1.6} = 2 $$ Divide the powers of ten: $$ 10^{-18} \div 10^{-19} = 10^{(-18 + 19)} = 10^{1} = 10 $$ Multiply these results: $$ n = 2 \times 10 = 20 $$ 7. **Answer:** There are 20 electrons in a charge of $3.2 \times 10^{-18}$ C. This means the charge is made up of 20 individual electrons, each contributing $1.6 \times 10^{-19}$ C.