A substance W has a concentration of 0.02mol when its molar mass was found to be74.0gmol-1 .Another valenve V contains 1.00×10^23 atom and has molar mass of 40.g mol^-1.
which of the two substance has greater mass +in grams) ? [l= 6.02×10^23]

ii) A 250Cm^3solution contains 14.65g of sodium chloride(Nacl) . calculate concentration of the solution in mol dm^3. [Na2=23 ,cl = 35.5].​