1. the atomic number of an element is the total number of which particles in the
nucleus? (1 point).
neutrons
protons
electrons
protons and electrons

2. all atoms of the same element have the same (1 point)
a. number of neutrons
b. number of protons
c. mass numbers
d. mass

3. isotopes of the same element have different (1 point)
a. positions on the periodic table
b. chemical behavior
c. atomic numbers
d. mass numbers