suiseth
contestada

A mystery element has 18 protons. Which one of the following statements is true about the element?
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A. The element belongs in row 2 of the periodic table and is classified as a halogen.
O
B. The element belongs in row 3 of the periodic table and is classified as a noble gas.
O
C. The element belongs in row 4 of the periodic table and is classified as an alkali metal.
D. The element belongs in row 5 of the periodic table and is classified as an alkaline earth metal.