you could produce a sample containing 2,400,000 free neutrons, what would it be 2658 seconds later?

Question

A) 300,000 neutrons, 2,100,000 protons, and 2,100,000 electrons. MY ANSWER

B) 300,000 neutrons and 2,100,000 protons

C) 300,000 neutrons, 2,100,000 protons, 2,100,000 neutrinos and 2,100,000 electrons.

D) 300,000 neutrons, 300,000 protons, and 300,000 electrons

am I correct
No one has answered this question yet.

Answer 1

The half life of a neutron is 10.8 minutes, or 648 seconds, according to one source I found. There seems to be some uncertainty about it, however. 2658 seconds is about 4 half lives. The number of neutrons left will be (1/2)^4 = 1/16 of the original value, or about 150,000. Your book seems to be using a different half life. Anyway, C is the best answer. Each decayed neutron turns into a proton, an electron and a neutrino.