7) Element Families on the Periodic Table have similar _______. There are Families.

8) Alkali Metals are good conductors of _ and ______________.

9) There are a total of _ elements that are grouped as Transition Metals.

10) As opposed to metals, non-metals can be very . They have no metallic

and do not reflect .

11) All Lanthanide Series elements occur naturally except for _.

12) All Actinide Series elements are _ and most are _________

The periodic table is an arrangement of elements in groups and periods based on their properties. The properties of elements repeat at regular intervals hence the term, "periodic".

The answers to the questions are;

7) Element Families on the Periodic Table have similar properties. There are 18 families.

8) Alkali Metals are good conductors of heat and electricity.

9) There are a total of 38 elements that are grouped as Transition Metals.

10) As opposed to metals, non-metals can be very opaque. They have no metallic luster and do not reflect light.

11) All Lanthanide Series elements occur naturally except for promethium.

12) All Actinide Series elements are radioactive and most are synthetic.

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