Question

Which of the following equals one atomic mass unit?
A) one-twelfth the mass of one carbon-12 atom
B) the mass of one electron
C) one-sixth the mass of one helium-4 atom
D) the mass of one carbon-12 atom

Answer 1

$\bf\huge\color{red}{ANSWER}$

Option (A) one-twelfth the mass of one carbon-12 atom is the right answer ✔️

Because one atomic mass unit (AMU) is equal to the one-twelfth the mass of one carbon-12 atom.

Answer 2

answer : option (A) one-twelfth the mass of one carbon-12 atom.

explanation : one atomic mass unit or, amu is equal to one-twelfth of the mass of Carbon - 12 isotope.

we know, mass of carbon -12 isotope = 12g/mol

so, atomic mass unit = 1/12 × 12g/mol

= 1g/mol

hence, one atomic mass unit is numerically equivalent to 1g/mol. actually, atomic mass unit or a.m.u is the mass of one nucleon (either a single proton or neutron).

hence, option (A) is correct.