This set of Solid State Chemistry Multiple Choice Questions & Answers (MCQs) focuses on “X-rays and their Generations”.
1. X-rays are ______________ of wavelength ~ 1 A˚ (10-10m).
a) Rays from visible region
b) Rays from proton
c) Electromagnetic radiation
d) Electric radiation
Explanation: X-rats are electromagnetic radiation. They occur in that part of the electromagnetic spectrum between ϒ-rays and the ultraviolet. X-rays are produced when high energy charged particles e.g. electrons accelerated through high voltage.
2. When electrons loses their energy and convert it into electromagnetic radiation.
a) Black radiation
b) White radiation
d) Blue radiation
Explanation: The electrons are slowed down or stopped by the collision and some of their lost energy is converted into electromagnetic radiation, such processes give ‘white radiation’.
3. Which of the following statements for X-rays?
a) X-rays have wavelength ranging upwards from lower limiting value
b) X-rays have wavelength ranging downwards from upper limiting value
c) X-rays occur when the kinetic energy is converted into the gamma radiation
d) X-rays are produce when low energy charged particles are accelerated
Explanation: X-rays have wavelengths ranging upwards from limiting value. This lower wavelength limit corresponds to the X-rays of highest energy and occurs when all the kinetic energy of the incident particles s converted into X-rays.
4. X-rays which in diffraction experiments leads to which of the following radiations?
a) Gamma radiation
b) Monochromatic gamma radiation
c) Monochromatic X-rays
Explanation: The X-rays which are used in almost all diffraction experiments are produced by a different process that leads to monochromatic X-rays. An electron in an outer orbital drops down to occupy he vacant 1s level and the energy in the transition appears as X-radiation.
5. For copper, the transition 2p→1s transition is known as______
Explanation: For copper, the transition 2p→1s, is called Kα, has a wavelength of 1.5418 A˚ and 3p→1s transition, Kβ, 1.3922 A˚. The Kα transition occurs much more frequently than the Kβ and it is these more intense Kα radiations which results that is used in diffraction experiments.
6. Which of the following statements is true for Kα transition?
a) It is singlet
b) It is doublet
c) It is triplet
d) It is four let
Explanation: Kα is a transition from 2p→1s, and it is a doublet because the transition has slightly different energy for the two possible spin states of the 2p electron while makes the transition, relative to the spin of the vacant 1s orbital.
7. What are the two features of X-ray emission spectrum of an element such as copper?
a) Monochromatic peaks and wavelength
b) X-ray radiation and frequency
c) Electric field and wavelength
d) Magnetic field and monochromatic peaks
Explanation: The X-ray emission spectrum of an element such as copper has two features. The intense, monochromatic peaks, caused by electronic transitions within the atoms, have wavelengths that are characteristic of the element i.e. copper. These monochromatic peaks are superposed on a background of ‘white radiation’.
8. In order to generate the monochromatic radiation, what is voltage required to accelerate the electrons?
Explanation: To generate the characteristic monochromatic radiation, the voltage used to accelerate the electrons need to be sufficiently high i.e. > or = 10kV so that ionization of the copper 1s electrons may occur.
9. In the X-ray tube which of the following element is used as window materials?
Explanation: In X-ray tube, the X-rays leave the tube through ‘windows’ made of beryllium. The absorption of X-rays on passing through materials depends on the atomic weight of the elements present in the material. Thus beryllium with an atomic number of 4 is therefore one of the most suitable window materials.
10. Which of the following statements is true for the Kα and Kβ radiation?
a) Iron transmit Kα and Kβ radiation
b) Zinc absorb Kα and Kβ radiation
c) Iron absorbs Kα and Kβ radiation
d) Zinc accelerate Kα and Kβ radiation
Explanation: A lighter element, such as iron, would absorb Kα and Kβ radiation because its absorption edge is displaced to higher wavelengths. On the other hand, a heavier element, such as zinc, would transmit both Kα and Kβ radiation while still absorbing much of the higher energy white radiation.
Sanfoundry Global Education & Learning Series – Solid State Chemistry.
To practice all areas of Solid State Chemistry, here is complete set of 1000+ Multiple Choice Questions and Answers.