Their atomic number increases
<span>The number of moles of Cl- ions needed to combine completely with 0.25 mole of Mg+2 ions is:
0.50.</span>
Magnesium. You can count the electrons in each level and because the number of electrons is the same with protons you have the atomic number based of which you can get the element in the periodic table
The correct answer is C 0.15 g/mL.
