Question

how many neutrons are in an atom of uranium - 235? answer: a 92 b 143 c 235 d 238.0

Explanation:

Step1: Recall uranium's atomic number

Uranium has an atomic number of 92, which is the number of protons.

Step2: Use neutron - proton relationship

The mass number of uranium - 235 is 235. Number of neutrons = Mass number - Number of protons. So, neutrons = 235 - 92.

Step3: Calculate the number of neutrons

235−92 = 143.

Answer:

B. 143