How does formula mass differ from atomic mass?
A)They represent the same thing.
B)The formula mass of a substance is the sum of the atomic masses of the elements is its chemical formula.The atomic mass is the mass of a single atom.
C)The atomic mass of a substance is the sum of the formula masses of the elements is its chemical formula.The atomic mass is the mass of a single atom.
D)The formula mass is the mass of the chemical formula and the atomic mass is the mass of the molecule.

Question

Quizplus · Accepted Answer

Formula mass and atomic mass represent two different things. Formula mass is the sum of the atomic masses of the elements in a chemical formula, while atomic mass is the mass of a single atom. For example, the formula mass of water (H2O) is 18.015 g/mol, which is the sum of the atomic mass of two hydrogen atoms and one oxygen atom. The atomic mass of hydrogen is 1.008 u, and the atomic mass of oxygen is 15.999 u. Therefore, the formula mass is 2(1.008 u) + 15.999 u = 18.015 g/mol.

How Does Formula Mass Differ from Atomic Mass