Question 21 Determine the number of molecules in 134 grams of NaCl. Be sure to show your work and highlight your answer.

## Step 1<br />First, we need to calculate the molar mass of NaCl. The molar mass of an element is the mass of one mole of that element. It is usually expressed in grams per mole (g/mol). The molar mass of NaCl is calculated by adding the molar mass of Sodium (Na) and Chlorine (Cl). The molar mass of Sodium (Na) is approximately 22.99 g/mol and the molar mass of Chlorine (Cl) is approximately 35.45 g/mol. Therefore, the molar mass of NaCl is \(22.99 g/mol + 35.45 g/mol = 58.44 g/mol\).<br /><br />## Step 2<br />Next, we need to calculate the number of moles of NaCl in 134 grams. This can be done by dividing the mass of NaCl by its molar mass. So, the number of moles of NaCl is \(134 g / 58.44 g/mol = 2.29 moles\).<br /><br />## Step 3<br />Finally, we need to calculate the number of molecules of NaCl. We know that one mole of any substance contains Avogadro's number of molecules, which is \(6.022 \times 10^{23}\) molecules. Therefore, the number of molecules of NaCl is \(2.29 moles \times 6.022 \times 10^{23} molecules/mole = 1.38 \times 10^{24} molecules\).