CBSE
Multiple Choice QuestionsIn nuclear explosion, the energy is released in the form of :
kinetic energy
electrical energy
potential energy
None of these
If the mass defect of is 0.090 u , then binding energy per nucleon is :
(1 u = 931.5 MeV)
9.315 MeV
931.5 MeV
83.0 MeV
8.38 MeV
From elementary molecular orbital theory we can deduce the electronic configuration of the singly positive nitrogen molecular ion as :
1s2 , 1s2 , 2s2 , 2s2 , 2p4 , 2p1
1s2 , 1s2 , 2s2 , 2s2 , 2p2 , 2p3
1s2 , 1s2 , 2s2 , 2s2 , 2p3 , 2p2
1s2 , 1s2 , 2s2 , 2s2 , 2p2 , 2p4
Which of the following arrangement is possible?
| n | l | m | s |
| 5 | 2 | 2 | +1/2 |
| 2 | 2 | 0 | -1/2 |
| 3 | -2 | 1 | +1/2 |
| 0 | 0 | 1 | +1/2 |
In a decay process changes into . Which process is this?
-decay
decay
- decay
- decay.
Assertion : For Balmer series of hydrogen spectrum, the value n1 = 2 and n2 = 3, 4, 5... .
Reason : The value of n2 for a line in Balmer series of hydrogen spectrum having the highest wavelength is 6.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
27Co60 is radioactive because :
its atomic number is high
it has high ratio
it has high ratio
None of the above
Threshold frequency of a metal is 5 1013 s-1 upon which 1 x 1014s-1 frequency light is focused. Then the maximum kinetic energy of emitted electron is
3.3 10-21
3.3 10-20
6.6 10-23
6.6 10-20
Which of the following pairs represent isotones?
The number of atoms in 52 g of He is
78.299 x 1024atoms
7.820 x 10-24atoms
7.829 x 1024 atoms
78.234 x 1025 atoms
