1) Protons, Neutrons, Electrons
1) Protons are positive, electrons are negative, and neutrons are neutral/have no charge
2) Identity
3) Protons, Electrons (neutral atom), same
4) mass number, nucleus
5) isotope, same
6) Lithium: LI, 3
Bromine: Br, 35
Iron: Fe, 26
Copper: Cu, 29
Oxygen: O, 8
Mercury: Hg, 80
Krypton: Kr, 36
Helium: He, 2
7) Uranium: U, 92
Chlorine: Cl, 17
Boron: B, 5
Iodine: I, 53
Antimony: Sb, 51
Xenon: Xe, 54
8) a. Iron (Fe)
b. Iodine (I)
c) Helium (He)
d) Calcium (Ca)
e) Lead (Pb)
f) Hydrogen (H)
9) a. Yes
b. No
c. Yes
d. No
hope this helps!