MCQ
Give electronic configuration of silicon.
- A$1 s^1 1 s^2 2 s^2 3 s^2 3 p^2 3 p^6$
- B$1 s^2 1 s^2 3 s^2 2 p ^4 3 s^2 3 p ^2$
- C$1 s^2 2 s^2 2 p^6 3 s^2 3 p^2$
- D$1 s^2 2 s^2 2 p^6 3 s^1 3 p^3$
✓
Answer
B. $1 s^2 2 s^2 2 p ^6 3 s^2 3 p ^2$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
An X-ray has a wavelength of 0.010 Å. Its momentum is
| (a) 2.126 × 10–23 kg-m/sec | (b) 6.626 × 10-22 kg-m/sec |
| (c) 3.456 × 20–25 kg-m/sec | (d) 3.313 × 10–22 kg-m/sec |
The correct curve between the stopping potential (V) and intensity of incident light (I) is
|
(a)
|
(b)
|
(c)
|
(d)
|
Einstein got Nobel prize on which of the following works
|
(a) Mass-energy relation |
(b) Special theory of relativity |
|
(c) Photoelectric equation |
(d) (a) and (b) both |
The grid voltage of any triode valve is changed from –1 volt to – 3 volt and the mutual conductance is 3 
mho. The change in plate circuit current will be
|
(a) 0.8 mA |
(b) 0.6 mA |
(c) 0.4 mA |
(d) 1 mA |
The fact that electric charges are integral multiples of the fundamental electronic charge was proved experimentally by
|
(a) Planck |
(b) J.J. Thomson |
(c) Einstein |
(d) Millikan |
The diffusion current in a p-n junction is:
- From the n-side to the p-side.
- From the p-side to the n-side.
- From the n-side to the p-side if the junction is forward-biased and in the opposite direction if it is reverse-biased.
- From the p-side to the n-side if the junction is forward-biased and in the opposite direction if it is reverse-biased.
An antenna behaves as resonant circuit only when its length is
|
(a) |
(b) |
|
(c) |
(d) |
A cell of negligible resistance and e.m.f. 2 volts is connected to series combination of 2, 3 and 5 ohm. The potential difference in volts between the terminals of 3 ohm resistance will be
|
(a) 0.6 |
(b) 2/3 |
(c) 3 |
(d) 6 |
Two long parallel wires P and Q are both perpendicular to the plane of the paper with distance 5 m between them. If P and Q carry current of 2.5 amp and 5 amp respectively in the same direction, then the magnetic field at a point half way between the wires is
|
(a) |
(b) |
(c) |
(d) |
A fish looking up through the water sees the outside world contained in a circular horizon. If the refractive index of water is 
and the fish is 12 cm below the surface, the radius of this circle in cm is
|
(a) 36 |
(b) 4 |
(c) 36 |
(d) 36/ |
