How many protons, neutrons, and electrons are in each of the following atoms or ions? a. \(_{12}^{24} \mathrm{Mg}\) b. \(_{12}^{24} \mathrm{Mg}^{2+}\) c. \(_{27}^{59} \mathrm{Co}^{2+}\) d. \(_{27}^{59} \mathrm{Co}^{3+}\) e. \(_{2}^{59} \mathrm{Co}\) f. \(_{34}^{79} \mathrm{Se}\) g. \(_{34}^{79} \mathrm{Se}^{2-}\) h. \(_{28}^{63} \mathrm{Ni}\) i. \(_{28}^{59} \mathrm{Ni}^{2+}\)

Protons are equal to the atomic number (Z) for each given atom or ion. Protons do not change when there's a charge. a. Protons in \(_{12}^{24} \mathrm{Mg}\): Z = 12 b. Protons in \(_{12}^{24} \mathrm{Mg}^{2+}\): Z = 12 c. Protons in \(_{27}^{59} \mathrm{Co}^{2+}\): Z = 27 d. Protons in \(_{27}^{59} \mathrm{Co}^{3+}\): Z = 27 e. Protons in \(_{2}^{59} \mathrm{Co}\): Z = 2 (Note: this atom is incorrect, the atomic number should match cobalt's 27) f. Protons in \(_{34}^{79} \mathrm{Se}\): Z = 34 g. Protons in \(_{34}^{79} \mathrm{Se}^{2-}\): Z = 34 h. Protons in \(_{28}^{63} \mathrm{Ni}\): Z = 28 i. Protons in \(_{28}^{59} \mathrm{Ni}^{2+}\): Z = 28

Neutrons are calculated by subtracting the atomic number (Z) from the mass number (A). a. Neutrons in \(_{12}^{24} \mathrm{Mg}\): A - Z = 24 - 12 = 12 b. Neutrons in \(_{12}^{24} \mathrm{Mg}^{2+}\): A - Z = 24 - 12 = 12 c. Neutrons in \(_{27}^{59} \mathrm{Co}^{2+}\): A - Z = 59 - 27 = 32 d. Neutrons in \(_{27}^{59} \mathrm{Co}^{3+}\): A - Z = 59 - 27 = 32 e. Neutrons in \(_{2}^{59} \mathrm{Co}\): A - Z = 59 - 2 = 57 (Note: this atom is incorrect, as the atomic number should match cobalt's 27) f. Neutrons in \(_{34}^{79} \mathrm{Se}\): A - Z = 79 - 34 = 45 g. Neutrons in \(_{34}^{79} \mathrm{Se}^{2-}\): A - Z = 79 - 34 = 45 h. Neutrons in \(_{28}^{63} \mathrm{Ni}\): A - Z = 63 - 28 = 35 i. Neutrons in \(_{28}^{59} \mathrm{Ni}^{2+}\): A - Z = 59 - 28 = 31

Electrons equal the number of protons, and when there's a charge, this number will change by the value of the charge. a. Electrons in \(_{12}^{24} \mathrm{Mg}\): Z = 12 b. Electrons in \(_{12}^{24} \mathrm{Mg}^{2+}\): Z - Charge = 12 - 2 = 10 c. Electrons in \(_{27}^{59} \mathrm{Co}^{2+}\): Z - Charge = 27 - 2 = 25 d. Electrons in \(_{27}^{59} \mathrm{Co}^{3+}\): Z - Charge = 27 - 3 = 24 e. Electrons in \(_{2}^{59} \mathrm{Co}\): Z = 2 (Note: this atom is incorrect, as the atomic number should match cobalt's 27) f. Electrons in \(_{34}^{79} \mathrm{Se}\): Z = 34 g. Electrons in \(_{34}^{79} \mathrm{Se}^{2-}\): Z + Charge = 34 + 2 = 36 h. Electrons in \(_{28}^{63} \mathrm{Ni}\): Z = 28 i. Electrons in \(_{28}^{59} \mathrm{Ni}^{2+}\): Z - Charge = 28 - 2 = 26