An imaginary radioactive element ₉₂X²³⁵ decays to form X₁, X₂, X₃, X₄, X₅ and X₆ nuclides, by ejecting two β-particles, followed by α-particles and again two β-particles, followed by α-particle. Represent the various nuclear change in the form of equation. State the mass number and atomic number of X₆. List the isotopes and isobars in the above nuclear equation.

State two factors on which the rate of emission of thermions depends.

The isotope of ₉₂U²³⁵ decays by alpha emission to an isotope of Thorium (Th). The Thorium isotope decays by beta emission to an isotope of Protactinium (Pa). Write down the equations to represent these two nuclear changes.

A mixture of radioactive substances gives off three types of radiations. (i) Name the radiations which are charged. (ii) Name the radiation similar in nature to cathode rays. (iii) Name the radiation similar in nature to X-rays. (iv) Name the radiation which is deviated most in a magnetic field. (v) Name the radiation which is not affected by an electric field. (vi) Name the radiation which has the maximum penetrating power. (vii) Name the radiation which has the highest ionising power. (viii) Name the radiation which has the highest speed. (ix) Name the radiation which when becomes neutral, become the atom of a rare gas.

State, giving reasons, whether the following nuclear decays are allowed or not?

The nucleus ₈₄X²⁰² emits an alpha particle and forms the nucleus Y. Represent this change in the form of an equation.

What changes will take place in the mass number and atomic number of the nucleus Y if it emits gamma radiations?

How does the position of an element change in the periodic table when it emits out an alpha particle?

What changes occur in the nucleus of a radioactive element when it emits an alpha particle? Show by an example?

What will an alpha particle change into when it absorbs: (i) One electron; (ii) Two electrons?

State three properties of α-rays.

What is the effect on the atomic mass and the atomic number of a radioactive element, after the emission of an α-particle?

When an alpha particle gains two electrons it becomes neutral and becomes an atom of an element which is a rare gas. What is the name of this rare gas?

An atomic nucleus A is composed of 84 protons and 128 neutrons. It emits an α-particle and is transformed into nucleus B. Write down the composition of B.

State charge and mass of (i) α-particle, (ii) β-particle.