Question

Calculate the molarity of water if its density is 1000 kg/m3

Answer 1

1 liter water =1 kg

or 1000 ml water =1 kg [Given d=1000kg/m3]

Moles of water present in 1000ml=1000/18=55.55

Hence molarity of water =55.55M

Answer 2

given that, 

             D= 1000kg/m^3

and         1m3= 1000 l 

so,       D= 1000kg/1000l = 1 kg/l

now,    1kg of water is present in 1l of solution 

now, no of moles of water=1000/18= 55.5 moles

so, molarity is 55.55 moles/l.


I Hope you got it