| Question (1):
Almost the entire mass of an atom is concentrated in the__________. |
| 1. |
proton
|
| 2. |
electrons
|
| 3. |
nucleus |
| 4. |
neutrons |
|
| Ans: 3 |
|
| Question (2):
Electron was discovered by___________. |
| 1. |
Chadwick
|
| 2. |
Thomson
|
| 3. |
Goldstein |
| 4. |
Bohr |
|
| Ans: 2 |
|
| Question (3):
An atom has a mass number of 23 and atomic number 11. The number of protons are_________. |
|
|
| Ans: 1 |
|
| Question (4):
The mass of the atom is determined by________. |
| 1. |
neutrons
|
| 2. |
neutron and proton
|
| 3. |
electron |
| 4. |
electron and neutron |
|
| Ans: 2 |
|
| Question (5):
The K, L and M shells of an atom are full. Its atomic number is_______. |
|
|
| Ans: 1 |
|
| Question (6):
Which of the air pressures is appropriate for the production of cathode rays in the discharge tube? |
| 1. |
1 cm Hg
|
| 2. |
1 mm Hg
|
| 3. |
0.001 cm Hg |
| 4. |
0.001 mm Hg |
|
| Ans: 4 |
|
| Question (7):
Cathode rays are deflected towards__________. |
| 1. |
positive electrode
|
| 2. |
negative electrode
|
| 3. |
both electrodes |
| 4. |
none of the electrodes |
|
| Ans: 1 |
|
| Question (8):
The absolute charge of an electron is___________. |
| 1. |
- 1.6 x 10-19C
|
| 2. |
+ 1.6 x 10-19C
|
| 3. |
1.6 x 10-19C |
| 4. |
16 x 10-19C |
|
| Ans: 1 |
|
| Question (9):
The proton is heavier than an electron by___________. |
| 1. |
1850 times
|
| 2. |
1840 times
|
| 3. |
1000 times |
| 4. |
100 times |
|
| Ans: 2 |
|
| Question (10):
Carbon-12 atom has_______________. |
| 1. |
6 electrons, 6 protons, 6 neutrons
|
| 2. |
6 electrons, 12 protons, 6 neutrons
|
| 3. |
12 electrons, 6 protons, 6 neutrons |
| 4. |
18 electrons, 6 protons and 6 neutrons |
|
| Ans: 1 |
|
| Question (11):
Chadwick got the Nobel Prize for the discovery of __________. |
| 1. |
protons
|
| 2. |
neutrons
|
| 3. |
electrons |
| 4. |
mesons |
|
| Ans: 2 |
|
| Question (12):
Mass number is equal to the_________. |
| 1. |
number of protons + number of electrons
|
| 2. |
number of protons + number of neutrons
|
| 3. |
number of neutrons + number of electrons |
| 4. |
number of electrons |
|
| Ans: 2 |
|
| Question (13):
The element X has 2 valence electrons. It is a____________. |
| 1. |
metal
|
| 2. |
non-metal
|
| 3. |
metalloid |
| 4. |
gas |
|
| Ans: 1 |
|
| Question (14):
The volume of the nucleus of an atom when compared to the extra nuclear part is_________. |
| 1. |
bigger
|
| 2. |
smaller
|
| 3. |
same size |
| 4. |
unpredictable |
|
| Ans: 2 |
|
| Question (15):
In Rutherford's alpha-scattering experiment, a foil of element that was used _______________. |
| 1. |
gold
|
| 2. |
silver
|
| 3. |
aluminum |
| 4. |
magnesium |
|
| Ans: 1 |
|
| Question (16):
An element has an electronic configuration of 2, 8, 7. Its valency is |
|
|
| Ans: 1 |
|
Question (17):
The other name of  is _________ |
| 1. |
protium
|
| 2. |
tritium
|
| 3. |
deuterium |
| 4. |
proton |
|
| Ans: 1 |
|
| Question (18):
During a chemical reaction, atomic number_________. |
| 1. |
changes
|
| 2. |
remains same
|
| 3. |
changes and then is restored |
| 4. |
changes alternately |
|
| Ans: 2 |
|
| Question (19):
The fixed circular paths around the nucleus are called_________. |
| 1. |
orbits
|
| 2. |
orbitals
|
| 3. |
nucleons |
| 4. |
mesons |
|
| Ans: 1 |
|
