Question

What is the mass of potassium hydroxide required to prepare 10L of a 2 mol/L solution

Answer 1

molarity = no. of moles / volume of solution in litres

=> 2= no. of moles/ 10

=> no. of moles= 2*10= 20

Now, no. of moles = given mass / molar mass

molar mass of KOH = 39+16+1= 56 gram/mol

therefore, no. of moles= mass/ 56

=> 20= mass/56

=> mass of KOH = 20*56= 1120 grams