The largest MCQs Website for CSS & PMS Exams

Roentgen discovered X-rays and Mosley found that the frequency of the X-rays emitted from anode increases with the

A. increase in the mass number of the metal used as anode
B. decrease in the mass number of the metal used as anode
C. decrease in the proton number of the metal used as anode
D. increase in the proton number of the metal used as anode

Show Answer…
Correct Answer: D. increase in the proton number of the metal used as anode
» Read More…

If a particle of mass 0.1gram moves with a velocity of 10,000 m/s then the wavelength of the wave associated with this particle is

A. 6.626 x 10-34 m
B. 2.145 x 10-39 m
C. 3.313 x 10-21 m
D. 1.325 x 10-18 m

Show Answer…
Correct Answer: A. 6.626 x 10-34 m
» Read More…

Second ionization energy

A. is always less than first ionization energy
B. is always greater than first ionization energy
C. is equal to the first ionization energy
D. may be greater or less than the first ionization energy depending on the nature of the element

Show Answer…
Correct Answer: B. is always greater than first ionization energy
» Read More…