Ch. 4.3 - Distinguishing Among Atoms

The number of _ in the nucleus of an atom is the atomic number of that element.

Because atoms are electrically neutral, the number of protons and _ in an atom are equal.

The total number of _ and neutrons in an atom is the mass number.

Atoms of the same element are identical in most respects, but they can differ in the number of _ in the nucleus.

Atoms that have the same number of protons, but different mass numbers are called _.

Calculate the atomic mass of bromine. The two isotopes of bromine have atomic masses and relative abundance of 78.92 amu (50.69%) and 80.92 amu (49.31%).

Round to four significant figures and include units of "amu".

Calculate the average atomic mass of oxygen given the following isotopes and their relative abundances.

Oxygen-16: 99.76%

Oxygen-17: 0.037%

Oxygen-18: 0.204%

Round to two significant figures and include units of "amu".