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.

Chemical energy

Explanation:

Campfires convert chemical energy stored in wood into thermal energy, which is useful for cooking food and staying warm. Nuclear energy generates a tremendous amount of thermal energy, which can be converted into electrical energy in a nuclear power plant.