Chemistry (Part-1)

Among the given options, the option (d) statement is incorrect because protium is not a rare isotope of hydrogen.

Hydrogen is the only element whose isotopes have different names independent of their name. D and T symbols are used for this. Hydrogen has three isotopes, which are easily obtained- Protium (¹$H₁$), deuterium (²H$₁$), and tritium (³H$₁$).

The fundamental particle that is not present in the nucleus of the most common isotope of a hydrogen atom (Protium) is the  Neutron.

The nucleus of a Protium atom (​¹H₁) consists of only one proton.
It has one electron orbiting the nucleus.
It has zero neutrons.

The radioactive isotope of hydrogen among the options is Tritium. 

Tritium (¹$H₃$) has one proton and two neutrons in its nucleus. This unstable neutron-to-proton ratio causes it to undergo radioactive decay, emitting a beta particle. 

A hydrogen atom has only one proton in its nucleus and one electron in its orbit. When hydrogen gives up this one electron, the nucleus remains, which is made up of a single proton. Hence the nucleus of the hydrogen atom is called proton.

The atomic number of all the give elements are as follows:

From the basic particles protons, neutrons, and electrons, only protons and neutrons are located in the nucleus, while electrons reside outside the nucleus in orbits around the nucleus.

Protons and electrons are positively charged and negatively charged particles respectively, whereas electrically neutral neutrons (without charge) particles.

The atomic number of an atom gives the number of  protons.

The atomic number (Z) is defined as the number of protons in the nucleus of an atom. This number uniquely identifies an element.  In a neutral atom, the number of protons is also equal to the number of electrons.

However, the defining characteristic of an element's atomic number is its proton count. The number of neutrons can vary (leading to isotopes), and the number of electrons can change (leading to ions).

The atomic number of the given elements is:

The following are the atomic numbers of the given elements:

Thus, the atomic number of zinc (30) is higher than that of copper (29).