How many protons, neutrons, and electrons are there in 70Se2-?

The answer to your question is Protons = 36, Neutrons = 26, Electrons = 36

Explanation:

⁷⁰Se²⁻

The number of protons is equal to the atomic number, Selenium has an atomic number of 34. Then the number of protons = 34.

The number of neutrons = Mass number - number of protons

= 70 - 34

= 36

The number of electrons = number of protons + 2 because of the 2 - next to the symbol of Selenium.

Number of electrons = 34 + 2

= 36