Ch. 4 Review

Front

How many valence electrons does sulfur have?

Back

Sulfur has 6 valence electrons.

Front

What must be true about an atom of beryllium and an atom of boron that have the same mass?

Back

They both have different numbers of protons and neutrons.

Front

When an atom forms an ion, what happens?

Back

It either gains or loses electrons to look like a noble gas.

Front

What is the most abundant isotope of phosphorus?

Back

Phosphorus-31.

Front

What is true about noble gases?

Back

They don't combine with other elements because they have full electron shells.

Front

What is the atomic number of phosphorus?

Back

The atomic number of phosphorus is 15.

Front

What is the average atomic mass of phosphorus?

Back

The average atomic mass of phosphorus is 30.97 amu.

Front

What defines an isotope?

Back

Isotopes are atoms of the same element with different numbers of neutrons.

Front

What is the significance of valence electrons?

Back

Valence electrons determine how an atom can bond with other atoms.

Front

What happens to an atom when it gains an electron?

Back

It becomes a negatively charged ion.