What is the charge on an ion with 21 protons, 30 neutrons, and 18 electrons. A.) 2+
B.) 3+
C.) 4+
D.) 4-

3+

Explanation:

Ignore neutrons.

Protons are positive and electrons are negative. To find a charge, it is protons minus electrons. In this atom, there are 21 protons and 18 electrons

21-18=3

Positive 3

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.