Question

25mL of ethanol (C2H3OH) is diluted to a volume of 150mL with water.

What is the concentration (in % v/v) of the following solution?

Answer 1

Amount of Ethanol = 25 mlAmount of Water = 75 ml
Total Volume = 25 ml+150 ml
= 175 ml

Percentage V/V = Amount of ethanol/Total volume x 100
= 25/75 * 100 %
= 14.2857%

Answer 2

volume of solute = 25 mL

Volume of solvent = 150 mL

% = ( volume of solute / volume of solvent ) x 100

% = ( 25 / 150 ) x 100

% = 0,166 x 100

= 16.6 % v/v

hope this helps!