What is the molarity of an ethanol solution containing 10.0g of ethanol in water with a total volume of 100ml?

2.17 moldm-3

Explanation:

Molarity is the number of moles of solute in a unit volume.

The atomic masses of

C -12

H-1

O-16

Therefore molar mass ( mass of 1 mol ) of ethanol ( CH3CH2OH )

( 12 x 2 ) + (1 x 6) + 16 = 46 g/mol

In 10 g of ethanol 10/46 mol should be present

So the molarity is (10/46) mol ÷ 100ml

= 10/ 46 mol ÷ 0.1 l

1L = 1 dm3

Therefore molarity = 10/46 mol ÷ 0.1 dm3

= 2.17 mol/dm3