How many protons does the isotope b have?

5

Because All atoms of boron always contain 5 protons, as that defines its atomic number 5, Boron atomic number 5 has five electrons in its ground state. The mass number for boron-11 is 11 (it's given to you), and recall that the number of protons plus the number of neutrons equals the mass number.

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.