2. what is the approximate mass of an atom that
contains 26 protons, 26 electrons and 19 neutrons?
a) 26 u b) 45 u c) 52 u d) 71 u
1
.

b. 45 u

Explanation:

the mass of an atom is equal to the protons plus neutrons:

26+19=45

hope this helps :)

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.