Test: Nuclei (March 10) - NEET MCQ

The nuclide (nucleus) consists of neutrons and protons (when combined called nucleons).
Thus,
No. of protons in 92U²³⁸ = 92,
No. of neutrons = 146 (238 – 92)
No. of nucleons = 238 (146 + 92)

R∝A^1/3
A(mass no.)=n+p
R/x=(10/80)^1/3
R/x=(1³/2³)^1/3
R/x=1/2
X=2R

The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of every atom of that element. The atomic number uniquely identifies a chemical element. It is identical to the charge number of the nucleus

For A nucleons
R=R_o​A^1/3 [R_o=constant]
 So, R∝A^1/3

The ratio of the volume of the atom and the volume of the nucleus is 10¹⁵
The radius of an atomic nucleus is of the order of 10⁻¹³cm or 10⁻¹⁵m or one Fermi unit.
On the other hand, the radius of an atom is of the order of 10⁻⁸cm or 10⁻¹⁰m or one angstrom unit.
Note:
The radius of the nucleus is much smaller than atomic radius.
The ratio of atomic radius to radius of nucleus is 10⁻¹⁰m /10⁻¹⁵m ​=10⁵
Volume is proportional to cube of radius.
The ratio of atomic radius to radius of nucleus is (10⁵)³=10¹⁵

James Chadwick set up an experiment to test his hypothesis. Chadwick put a piece of beryllium in a vacuum chamber with some polonium. The polonium emitted alpha rays, which struck the beryllium. When struck, the beryllium emitted the mysterious neutral rays.

Nucleus of hydrogen has only one proton. Hence its binding energy will be zero. The nuclear binding energy is the energy it takes to separate all the nucleons in a nucleus from each other. Since there is only the one nucleon, it's already separated from any other nucleons.

The fusion of hydrogen into helium is more likely to take place at high temperature and high pressure, like the sun.

The sum of the atomic no. and atomic mass no. on the reactant and product should be equal .
therefore 9+4 = a+1
a = 12

Nuclear forces are short range forces. This is the only correct answer. Others are wrong. They are the strongest forces in nature and do not obey inverse square law.