Which element consists of positive ions immersed in a “sea” of mobile electrons? A.
Sulfur
B.
Nitrogen
C.
Calcium
D.
Chlorine

A positive ion is an atom or a molecule that has a net positive charge. The charge of the proton in an atom or a molecule is positive.

A subatomic found in the atom or the molecule that lacks a positive charge is called an electron.

The correct answer is:

Option C. Calcium

This can be explained by:

Calcium is the only metal found in the given list and hence is the answer.

To learn more about electrons, protons and metals follow the link:

link

Calcium

Explanation:

Calcium is the only metal here

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