Chemistry A Unit 4 Practice Test

Front

How many electrons does Ba²⁺ have?

Back

54 electrons. Ba²⁺ has lost 2 electrons from its neutral state (which has 56 electrons).

Front

What ion does nitrogen typically form?

Back

N^-3. Nitrogen gains 3 electrons to achieve a stable electron configuration.

Front

Which elements have the most similar chemical properties?

Back

O and S. They are in the same group of the periodic table.

Front

How does electronegativity change across a period and down a group?

Back

Electronegativity increases across a period and decreases down a group.

Front

According to the octet rule, how many valence electrons do most elements need?

Back

8 valence electrons. Most elements strive to have a full outer shell.

Front

What is the octet rule?

Back

The octet rule states that atoms tend to gain, lose, or share electrons to achieve a full outer shell of 8 electrons.

Front

What is electronegativity?

Back

Electronegativity is the ability of an atom to attract electrons in a chemical bond.

Front

What is the charge of a neutral nitrogen atom?

Back

0. A neutral nitrogen atom has 7 protons and 7 electrons.

Front

What happens to the size of atoms as you move down a group in the periodic table?

Back

The size of atoms increases as you move down a group due to the addition of electron shells.

Front

What is the significance of the periodic table's groups?

Back

Elements in the same group have similar chemical properties due to having the same number of valence electrons.