2 Answers

Josh Gust · Answer 1 · 2019-04-07T22:43:40+0000

Answer:

Molarity of solution is 1.5501

Given data:

Molarity of NaOH = ?

Volume of solution = 250 ml

Mass of solute = 15.5 grams

Solution:

Formula:

Molarity = Mass of solute/Molar mass of solute * 1/volume of solution in liters.

First convert volume into Liters = 250/1000 =0.25 L

Now put the values in formula:

Molarity of NaOH = 15.5/39.997 * 1/0.25

= 1.5501

Molarity of NaOH = 1.55011

Chuim · Answer 2 · 2019-04-12T03:14:05+0000

The molar concentration of the solution is 1.55 mol/L.

1. Convert grams to moles.

$\text{Moles of NaOH} = 15.5 \text{g NaOH} * \frac{\text{1 mol NaOH}}{\text{40.00 g NaOH}} = \text{0.3875 mol NaOH}\\$

2. Convert millilitres to litres

$V = 250.0 \text{mL} * \frac{\text{1 L}}{\text{1000 mL}} = \text{0.2500 L}\\$

3. Calculate the molar concentration (c)

$c = \frac{\text{moles}}{\text{litres}} = \frac{\text{0.2875 mol}}{\text{0.2500 L}} = \textbf{1.55 mol/L}$