Question

A radioactive nucleus undergoes a series of decay according to the scheme $ {A ->[\alpha] A1}$$ { ->[\beta] A2}$$ { ->[\alpha] A3}$$ { ->[\gamma] A4}$ If the mass number and atomic number of A are 180 and 72 respectively, these numbers of $A_4$ are

• A. 172, 69
• B. 177, 69
• C. 171, 69
• D. 172, 68

Answer 1

The Correct Option is A

Decrease in mass number due to two $a = 2 ? 4 = 8$ Decrease in charge number due to two $a = 4$ Increase in charge number due to one $? = 1$ Net decrease in charge number $= 4 - 1 = 3$ $?$ affects neither. $\therefore$ For $A_{4}, A = 180 - 8 = 172$ $Z = 72 - 3 = 69$

Answer 2

We have been provided a reaction sequence in which an element is affected by alpha, beta, and gamma particles. These particles work in a certain order to cause the atom 'A' to decay four times: first the alpha particle, then the beta particle, then the alpha particle once again, and finally the gamma particle, which creates the product A₄.

These particles interact with atom A and subsequently lower their mass and atomic number by a factor of three, beta, and gamma times, respectively.

Taking 'A' as an example, its mass number and atomic number are 180 and 72, respectively. From this value of A, we shall subtract the mass and atomic number of the particles.

The atomic and mass numbers of:

Ɑ= 4,+2

𝝱= 0,-1

𝛄= 0,0

The total number of protons in an element's atom is indicated by its atomic mass number. It is believed that protons and neutrons both dwell in the nucleus of an atom. Therefore, it may be argued that the number of protons in an atom's nucleus determines its atomic mass number. Atomic mass number = total number of protons in the atom is the simplest way to express it.

The atomic and mass numbers of:

The symbol for the atomic mass number, "A," may be represented as "atomic mass number = the total number of protons in the atom."

Due to the fact that every atom has an identical atomic mass number, it may be used to identify an element.

Every element has a unique, identical atomic mass number, which may be used to identify an element.

The total amount of protons and neutrons (or nucleons) in the atom makes up the mass number.

Z stands for the mass number, which can be stated as easily as The mass number = Total number of nucleons.

The relationship between the mass number and the atomic mass number is Z = A + n.