General
✓✗Which of the following fluoro-anions does not exist?
- [AlF6]3−
- [BF6]3−
- [GaF6]3−
- [BF4]−
General
✓✗Match List I (allotrope) with List II (feature).
Choose the correct answer from the options given below.
| List I | List II |
| P. Diamond | I. Soccer-ball shaped molecule |
| Q. Graphite | II. Three-dimensional network, insulator |
| R. Fullerene C60 | III. Layers, good conductor |
| S. Carbon black (amorphous) | IV. Microcrystalline graphite, used as a black pigment |
- P-II, Q-III, R-I, S-IV
- P-III, Q-II, R-I, S-IV
- P-II, Q-I, R-III, S-IV
- P-I, Q-III, R-II, S-IV
General
✓✗Which of the following combinations shows the correct trend down group 14 from C to Pb?
A. Metallic character increases.
B. Catenation increases.
C. Stability of the +2 state increases.
D. Acidic character of the dioxides decreases.
Choose the correct answer from the options given below.
A. Metallic character increases.
B. Catenation increases.
C. Stability of the +2 state increases.
D. Acidic character of the dioxides decreases.
Choose the correct answer from the options given below.
- A, C and D only
- A, B and C only
- B and D only
- A, B, C and D
General
✓✗Which of the following oxides is acidic?
- CaO
- SnO
- PbO
- CO2
General
✓✗In which of the following pairs is the first oxide more acidic than the second?
- PbO, CO2
- Al2O3, B2O3
- Tl2O, Ga2O3
- B2O3, Al2O3
General
✓✗Arrange the following oxides in increasing order of acidic character: Al2O3, B2O3, Tl2O, In2O3
- B2O3 < Al2O3 < In2O3 < Tl2O
- In2O3 < B2O3 < Al2O3 < Tl2O
- Al2O3 < Tl2O < B2O3 < In2O3
- Tl2O < In2O3 < Al2O3 < B2O3
General
✓✗Match List I (element) with List II (nature).
Choose the correct answer from the options given below.
| List I | List II |
| P. Carbon | I. Metal |
| Q. Silicon | II. Typical non-metal forming CO and CO2 |
| R. Germanium | III. Metalloid |
| S. Lead | IV. Non-metal, second most abundant element in the crust |
- P-II, Q-IV, R-III, S-I
- P-II, Q-III, R-IV, S-I
- P-I, Q-IV, R-III, S-II
- P-IV, Q-II, R-III, S-I
General
✓✗The atomic radius of Ga is slightly less than that of Al because of
- poor shielding by the 3d electrons in Ga
- lanthanoid contraction
- the larger nuclear size of Al
- the inert pair effect
General
✓✗Which group 14 element is a typical non-metal?
- Lead
- Tin
- Germanium
- Carbon
General
✓✗Which group 13 element has an unusually low melting point (about 303 K) and stays liquid over a wide temperature range?
- Gallium
- Boron
- Aluminium
- Thallium
General
✓✗Boron forms only covalent compounds mainly because of its
- low electronegativity
- metallic nature
- small size and high ionisation enthalpies
- large size
General
✓✗In aqueous solution, Tl3+ is
- neither oxidising nor reducing
- a strong oxidising agent
- unstable only because it hydrolyses
- a strong reducing agent
General
✓✗The thermal stability of the tetrahalides of group 14 elements generally
- remains constant
- decreases down the group
- is maximum for PbX4
- increases down the group
General
✓✗The melting points of group 14 elements decrease down the group because
- the strength of interatomic bonding decreases as atomic size increases
- atomic mass decreases
- all of them form molecular solids
- the inert pair effect increases melting points
General
✓✗Which property of carbon is mainly responsible for the existence of a very large number of organic compounds?
- Its ability to form ionic bonds
- Its metallic nature
- Its large size
- Catenation together with tetravalency and multiple bonding