6.023 x 1022 molecules are present in 10 g of a substance ‘Y’. The molarity of a solution containing 5 g of substance ‘Y’ in 2 L solution is ______ x 10-3.
6.023×1022 molecules in grams
6.023×1023 molecules are present in 100 gms
Molecular mass of substance ‘Y’ = 100 gms
M=5100×2=0.025=25×10−3