Average Atomic Mass

Front

What is average atomic mass?

Back

The weighted average of the masses of an element's isotopes, taking into account their relative abundances.

Front

How do you calculate average atomic mass from isotopes?

Back

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

Front

If an isotope has a mass of 4 amu and is 30% abundant, what is its contribution to the average atomic mass?

Back

0.30 * 4 amu = 1.2 amu.

Front

What is the average atomic mass of an element with two isotopes: 10.013 amu (19.9% abundance) and 11.01 amu (80.1% abundance)?

Back

10.812 amu.

Front

What is the significance of isotopes in calculating average atomic mass?

Back

Isotopes have different masses and abundances, which affect the overall average atomic mass of an element.

Front

What does it mean for an element to have isotopes?

Back

Isotopes are variants of the same element that have the same number of protons but different numbers of neutrons.

Front

How can you identify isotopes of the same element?

Back

Isotopes of the same element have the same atomic number but different mass numbers.

Front

What is the mass number of an isotope?

Back

The total number of protons and neutrons in the nucleus of an atom.

Front

If an element has an average atomic mass of 41.97 amu, what can you infer about its isotopes?

Back

The isotopes contribute to this average based on their masses and relative abundances.

Front

What is the formula for calculating the contribution of an isotope to average atomic mass?

Back

Contribution = (mass of isotope) * (relative abundance).