Practice Concentration in Chemistry

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Worksheet PDF Free Answer-key PDF Family

Quick Recap

The quantity of solute dissolved per unit volume of solution, most commonly expressed as molarity ( $M$ ) in units of moles per liter (mol/L).

How 'strong' a solution is—more solute in the same volume = more concentrated.

Showing a random 20 of 50 problems.

Example 1

easy

How many moles of solute are in 2 L of a 3 M solution?

Example 2

hard

In the reaction

2\text{HCl} + \text{Ca(OH)}_2 \rightarrow \text{CaCl}_2 + 2\text{H}_2\text{O}

, what volume of

0.200\,\text{M}

HCl neutralizes

25.0\,\text{mL}

0.150\,\text{M}

\text{Ca(OH)}_2

Example 3

easy

Express

750\,\text{mL}

in liters.

Example 4

easy

A solution contains

0.80

mol of

\text{KBr}

4.0\,\text{L}

of solution. What is its molarity?

Example 5

easy

Compute the molarity when

0.040

mol of

\text{AgNO}_3

is dissolved in enough water to make

250\,\text{mL}

of solution.

Example 6

easy

How many moles of solute are in

400\,\text{mL}

of a

0.50\,\text{M}

solution?

Example 7

easy

What volume (L) of 2 M solution contains 4 mol of solute?

Example 8

challenge

0.500\,\text{L}

sample of

0.200\,\text{M}

\text{H}_2\text{SO}_4

is fully neutralized by

\text{NaOH}

via

\text{H}_2\text{SO}_4 + 2\text{NaOH} \rightarrow \text{Na}_2\text{SO}_4 + 2\text{H}_2\text{O}

. What mass of NaOH (

40.0\,\text{g/mol}

) is consumed?

Example 9

challenge

2NaOH + H_2SO_4 \rightarrow Na_2SO_4 + 2H_2O

, what volume of 0.5 M

H_2SO_4

neutralizes 0.02 mol NaOH?

Example 10

medium

Molarity of 117 g NaCl (

M=58.5

) dissolved to 2 L solution?

Example 11

challenge

How many grams of

CaCl_2

(

M=111

) are in 250 mL of a 0.4 M solution?

Example 12

easy

What is the molarity of 2 mol of solute in 1 L of solution?

Example 13

medium

How much water to add to 100 mL of 6 M to make 2 M?

Example 14

medium

Dissolving

9.8\,\text{g}

\text{H}_2\text{SO}_4

(molar mass

98\,\text{g/mol}

) to make

200\,\text{mL}

of solution gives what molarity?

Example 15

challenge

200\,\text{mL}

sample of

0.50\,\text{M}

NaCl is evaporated to

50\,\text{mL}

. Assuming no NaCl is lost, find the new molarity.

Example 16

easy

How many moles in 0.5 L of 0.2 M solution?

Example 17

medium

Dilute

50\,\text{mL}

4.0\,\text{M}

HCl to a final volume of

500\,\text{mL}

. What is the new molarity?

Example 18

easy

Molarity of 1 mol solute in 500 mL solution?

Example 19

challenge

Mixing 200 mL of 0.5 M NaCl with 300 mL of 1 M NaCl. Final molarity?

Example 20

easy

Does molarity use the volume of solvent or of solution?

← Back to Concentration Worked Examples Formula Explained

Related Concepts

Mole Solution Dilution Titration