Question

(1) How do you account for the fact that gram atomic mass or gram molecular mas of any substance contains the same number of particles?

(2) How many (a) molecules (b) hydrogen atoms (c) oxygen atoms are there in 0.5 mole of water?

Answer 1

Dear student,
1. Gram atomic mass is the atomic mass of an element in grams.
Gram molecular mass is the molecular mass of a substance in grams. It is the sum toatal of all the atomic masses in the molecular formula of a compound in grams.
2. 1 mole contains 6.02*10^23 atoms.
0.5 moles of water contains 2*0.5 moles of hydrogen atoms. Total no: of hydrogen atoms = 2*0.5* 6.02*10^23 = 6.02*10^23
0.5 moles of water contains 1 oxygen atom.(1*0.5 moles of oxygen atom) Total no: of oxygen atoms = 0.5*6.02*10^23 = 3.01*10^23
Regards