how calculate mass of solute

in 0.5dm^{3 of 0.5mol/dm}3

The useful formula for mole concept are here. Try manipulating it. Wink

how calculate molar mass(is it like oxygen is 16 then O2 is 32)? and mass of solute

dm^3 cancel out so left with 0.5*0.5moles=0.25moles.

mass=no of moles * Molar mass=0.25*Mr of the chemical=Answer

0.5mol/dm^3 * 0.5dm^3 =0.25mol

0.25mol * Mr = your answer