Answer:
1340 mg
Explanation:
concentration is the number of moles of solute in a 1000 mL of solution
the concentration of KCl solution is 1.20 M
There are 1.20 mol in 1000 mL of solution
a volume of 1000 mL contains - 1.20 mol
therefore 15 mL solution contains - 1.20 mol / 1000 mL x 15 mL = 0.018 mol
the molar mass of KCl is - 74.5 g/mol
mass of 1 mol is - 74.5 g
therefore mass of 0.018 mol is - 74.5 g/mol x 0.018 mol = 1.34 g
1000 mg - 1 g
therefore 1.34 g in milligrams is - 1.34 g x 1000 mg/g = 1340 mg
