Question

To soften cloths in the wash it is recommended to use 2.0 g of sodium borate per liter of water. If a filled washing machine holds 10 L of water and the correct amount of sodium borate per liter is added, what is the concentration in percent mass/volume of the solution?

Answer 1

% m/v of the solution = 0.2%m/v

Further explanation

`\tt Percent~m/v=(mass~solute(g))/(volume~solution(ml))* 100\%`

or

% m/v = g solute / 100 ml solution

Concentration : 2 g sodium borate / L water

For 10 L⇒20 g Sodium borate

`\tt \%m/v=(20~g)/(10,000~ml)* 100\%\\\\\%m/v=0.2\%`