Question

the molecular mass of a substance is the sum of the atomic masses of all the atoms in its molecule true or false ​

Answer 1

Answer:Molecular mass or molecular weight is the mass of a molecule. It is calculated as the sum of the mass of each constituent atom multiplied by the number of atoms of that element in the molecular formula.

Explanation:Follow me

Answer 2

Answer:

true

because molecular mass of of a substance is the sum of the atomic masses of all the atoms in the molecules .

For example : in H2O there are two atoms of hydrogen and one atom of Oxygen.

The atomic mass of hydrogen is one and the atomic mass of oxygen is 16.

mass of 2 atoms of hydrogen : 1*2

Mass of one atom of oxygen : 16*1

molecular mass of water (H2O): 2+16

=18

so the statement is true

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