Which of the following solutions have the same concentration?

Molarity (M) = Weight of NaOH×1000 Molecular weight of NaOH×V( in mL)=20×100040×200=2.5M (b) M=0.5×1000200=2.5M (c) M=40×100040×100=10M (d) M=20×100056×200=1.785MThus, 20 g NaOH in 200 mL of solution and 0.5 mole of KCI in 200 mL have the same concentration