# 2. How many grams of NaCl are required to prepare 0.40 L of a 0.75 M solution?

Okay class, today we're going to learn about calculating the mass of a NaCl solution needed to make a 0.75 M solution with a volume of 0.40 L. The mass you need is 17.55g, and I'm going to show you how to calculate it. To find the mass, we first need to calculate the number of moles using the formula: molarity = no of moles ÷ volume. Plugging in the numbers we have, we get 0.75 = no of moles ÷ 0.40. Solving for no of moles, we get 0.3 moles. To find the mass, we then multiply the number of moles by the molar mass of NaCl, which is 58.5 g/mol. So, mass of NaCl = 0.3 moles x 58.5 g/mol = 17.55g. And that's how you calculate the mass of a NaCl solution needed to make a 0.75 M solution with a volume of 0.40 L. If you want to learn more about mass calculation, check out brainly.com/question/19694949.