# How many grams of solid sodium hydroxide are required to make 175.00 mL of a 0.5100 M NaOH solution?

Mar 10, 2016

You will require 3.570 g of $\text{NaOH}$.

#### Explanation:

Step 1. Calculate the moles of $\text{NaOH}$.

You know there are 0.5100 mol of $\text{NaOH}$ in 1 L of solution.

In 175.00 mL of solution there are

$\text{0.175 00" cancel("L soln") × "0.5100 mol KCl"/(1 cancel("L soln")) = "0.089 25 mol NaOH}$

Step 2. Calculate the mass of $\text{NaOH}$.

The mass of 1 mol of $\text{NaOH}$ is $\text{(22.99 + 16.00+ 1.008) g = 40.00 g}$.

So the mass of $\text{0.089 25 mol of NaOH}$ is

$\text{0.089 25" cancel("mol NaOH") × "40.00 g NaOH"/(1 cancel("mol NaOH")) = "3.570 g NaOH}$