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?

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 protons in determining an element's identity?

Back

The number of protons in an atom's nucleus defines the element and its position on the periodic table.

Front

If an element has 33 protons, what is its atomic number?

Back

33, as the atomic number is equal to the number of protons.

Front

What is the mass number of an isotope?

Back

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

Front

How do you determine the number of neutrons in an isotope?

Back

Subtract the atomic number (number of protons) from the mass number.

Front

What is the average atomic mass of an element with isotopes of 75.23 amu (24.1%), 74.61 amu (48.7%), and 75.20 amu (27.2%)?

Back

To find the average atomic mass, calculate: (0.241 * 75.23) + (0.487 * 74.61) + (0.272 * 75.20).

Front

What does it mean if an average atomic mass is not a whole number?

Back

It indicates the presence of multiple isotopes with different masses and their relative abundances.

Front

What is the average atomic mass of silicon?

Back

28.09 amu.