Question

What is the molarity of a solution made from 0.250 mol of sodium hydroxide and 500 mL of water?

Answer 1

Answer:

$\boxed {\boxed {\sf 0.5 \ M \ NaOH}}$

Explanation:

Molarity is a measure of concentration in moles per liter.

$molarity= \frac{moles}{liters}$

There are 0.250 moles of sodium hydroxide (NaOH) and 500 milliliters of water. We need to convert milliliters to liters. Remember that 1 liter contains 1000 milliliters.

$\frac{1 \ L}{1000 \ mL}$

$500 \ mL*\frac{1 \ L}{1000 \ mL}$

$500*\frac{1 \ L}{1000 }$

$\frac{500}{1000} \ L=0.5 \ L$

Now we have the values to solve for molarity:

• moles= 0.250 mol NaOH
• liters= 0.5 L

Substitute the values into the formula.

$molarity= \frac{0.250 \ mol \ NaOH}{0.5 \ L}$

Divide.

$molarity= 0.5 \ mol \ NaOH/ L$

• 1 mole per liter (mol/liter) is equal to 1 Molar or M.
• Our answer of 0.5 moles of sodium hydroxide per liter is equal to 0.5 M NaOH

$molarity= 0.5 \ M \ NaOH$

The molarity of the solution is 0.5 M NaOH