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Nuclear Radius - Multiple Choice Questions

Q1. The radius of a nucleus of the iron nuclide is 4.35 × 10−15 m.

What is the radius of a nucleus of the uranium nuclide ?

A 2.69 × 10−15 m
B 2.89 × 10−15 m
C 6.55 × 10−15 m
D 7.05 × 10−15 m

 

Protons and neutrons within a nucleus are packed together with the same minimum distance as each other - nuclear density is constant.

Therefore the nuclear radius is related to the volume of the nucleus - which is proportional to the number of nucleons within it.

V ∝r3

so N ∝r3

56/(4.35 × 10−15)3 = 238/r3

r3 = 238 x (4.35 × 10−15)3/56

r3 = 3.50 x 10-43

r = 7.05 × 10−15 m

Choice D