Calculating Average Atomic Mass

Front

What is average atomic mass?

Back

The weighted average mass of an element's isotopes, measured in atomic mass units (amu).

Front

How do you calculate average atomic mass?

Back

Multiply the mass of each isotope by its relative abundance (as a decimal), then sum these values.

Front

What is an isotope?

Back

Atoms of the same element that have the same number of protons but different numbers of neutrons.

Front

What is the significance of relative abundance in calculating average atomic mass?

Back

Relative abundance indicates how common each isotope is in nature, affecting the average atomic mass.

Front

If an element has two isotopes with masses of 10 amu (90% abundance) and 12 amu (10% abundance), what is the average atomic mass?

Back

10.2 amu.

Front

What is the average atomic mass of an element with isotopes of 35 amu (75% abundance) and 37 amu (25% abundance)?

Back

35.5 amu.

Front

What does amu stand for?

Back

Atomic mass unit, a standard unit of mass that quantifies mass on an atomic or molecular scale.

Front

What is the average atomic mass of silver?

Back

107.8677 amu.

Front

What is the average atomic mass of an element with isotopes of 35.00 amu, 36.00 amu, and 38.00 amu with unknown abundances?

Back

Impossible to tell without relative abundances.

Front

What is the average atomic mass of atom X with 4.35% of 39.946 amu, 83.79% of 41.941 amu, 9.50% of 42.941 amu, and 2.36% of 43.939 amu?

Back

41.97 amu.