Question

what is the fraction of the mass of water due to nuetrons ?

Answer 1

Water(H2O) =total mass = 1+1+16 =18g/mol
no. of neutrons in H= 0 ( in protium)
no. of neutrons in O= 8 i.e 8 g/mol
Total neutrons in water(H2O)  = (2x0)+(1x8) = 8 g/mol
% mass neutrons in water= (8/18)= 0.044= 44.44%


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