The radius of a spherical nucleus as measured by electron scattering is 3.6 fm. What is the mass number of the nucleus most likely to be ?

Options

A. `"1 proton "+"2 neutrons"`
B. `"1 proton "+"1 neutrons"`
C. `"2 protons "+"1 neutron"`
D. `"2 protons "+"2 neutrons"`

Answer

A

Explanation

Nuclear radius, `R=R_(0)(A)^(1//3)`
where A is the mass number of a nucleus.
Given : `R=3.6nm`
`therefore" 3.6 fm "=(1.2fm)(A^(1//3))" "[because R_(0)=1.2fm]`
`"or "A=(3)^(2)=27`