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Solutions and concentrationChemistryHigh schoolabout 0:45

0.05 mol of solute is dissolved to make 500 mL of solution. What is the molarity?: animated lesson

A narrated, step-by-step solutions and concentration video lesson with captions. Final answer: M = 0.1 mol/L.

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Video with a synthetic English voice and captions. Pick another language for subtitles in that language, or open the interactive version.

Video narrated by a synthetic voice (Piper TTS, en_US-ljspeech-high voice (LJ Speech dataset, public domain)); the steps come from our maths engine and the answer was checked independently. Download MP4 (0.3 MB) · Captions (WebVTT)

Steps on screen

1. The problem
Worked example
0.05 mol of solute is dissolved to make 500 mL of solution. What is the molarity?
2. Step by step
1. $V = \frac{500\ \text{mL}}{1000} = 0.5\ \text{L}$
  Convert the volume to litres
2. $M = \frac{n}{V} = \frac{0.05\ \text{mol}}{0.5\ \text{L}} = 0.1\ \text{mol/L}$
  Molarity is moles per litre
3. The answer
$\text{M = 0.1 mol/L}$
M = 0.1 mol/L
4. Check
- n = MV: 0.1 × 0.5 = 0.05 mol ✓

Transcript

The problem. Here is the problem: 0.05 mol of solute is dissolved to make 500 mL of solution. What is the molarity? Molarity is moles of solute per litre of solution.

Step by step. Convert the volume to litres. Molarity is moles per litre.

The answer. So the answer is M equals 0.1 mol/L. Molarity (mol/L, written M) uses the volume of the whole solution, not of the solvent alone. To make a solution, weigh the solute, dissolve it in less solvent, then top up to the final volume.

Check. n equals MV: 0.1 times 0.5 equals 0.05 mol, which checks out.

About solutions and concentration

Molarity, dilution and moles of solute in a solution.

0.05 mol of solute is dissolved to make 500 mL of…