Elements in the same family on the periodic table —

A. have completely different properties
Incorrect. Elements in the same groups or families have similar properties.

B. have similar properties
Correct!

C. are found in the same period
Incorrect. Families or groups are found in the same column on the periodic table.

D. are grouped in a horizontal row
Incorrect. Families or groups are found in the same vertical column on the periodic table.

What do elements that are in the same period have in common?

A. They have the same number of energy levels.
Correct! Elements in the same period have the same number of energy levels.

B. They have the same number of protons.
Incorrect. Each element has a unique number of protons.

C. They have the same number of valence electrons.
Incorrect. Elements in the same group have the same number of valence electrons.

D. They have the same number of neutrons in the nucleus.
Incorrect. Elements in the same period have the same number of energy levels.

Why do lithium, sodium and potassium have similar chemical properties? Click here to access the periodic table.

A. They have the same number of energy levels.
Incorrect. These elements do not have the same number of energy levels. The number of energy levels does not determine the chemical properties of an element.

B. They have the same number of protons.
Incorrect. Each element has a unique number of protons.

C. They have the same number of valence electrons.
Correct!

D. They have the same number of neutrons in the nucleus.
Incorrect. The number of neutrons does not determine the chemical properties of an element.

Which of the following elements has properties most similar to calcium? Click here to access the periodic table.

A. potassium
Incorrect. Potassium does not have similar properties to calcium.

B. scandium
Incorrect. Scandium does not have similar properties to calcium.

C. sodium
Incorrect. Sodium does not have similar properties to calcium.

D. magnesium
Correct! Magnesium is in the same group or family as calcium so they have similar properties.

Which group contains the most reactive elements? Click here to access the periodic table.

A. alkali metals
Correct!

B. transition metals
Incorrect. The transition metals are not the most reactive elements.

C. noble gases
Incorrect. The noble gases are not the most reactive elements.

D. alkaline earth metals
Incorrect. The alkaline earth metals are not the most reactive elements.