Aluminium becomes passive in nitric acid because it-
1. Is a noble metal
2. Forms a thin film of oxide
3. Has a positive reduction potential
4. None of the above
The stability of the +1 oxidation state increases in the sequence:
1. Al <Ga<In<Tl
2. Tl<In<Ga<Al
3. In<Tl<Ga<Al
4. Ga<In<Al<Tl
Borax bead test is responded by:
1. Divalent metals
2. Heavy metals
3. Light metals
4. Metal which forms coloured metaborates
Match the species given in Column I with the properties mentioned in Column II.
| Column I | Column II | 
| A. \(\text{BF}^-_4\) | 1. Oxidation state of the central atom is +4 | 
| B. AlCl3 | 2. Tetrahedral shape | 
| C. SnO | 3. Lewis acid | 
| D. PbO2 | 4. Can be further oxidized | 
Codes:
| A | B | C | D | |
| 1. | 2 | 3 | 4 | 1 | 
| 2. | 1 | 2 | 3 | 4 | 
| 3. | 1 | 4 | 3 | 2 | 
| 4. | 4 | 1 | 3 | 2 | 
Aluminium chloride in acidified aqueous solution forms a complex 'A'.
The formula of A and hybridisation state of Al in 'A' is respectively:
1. [Al(H2O)6]3+, sp3d2
2. [Al(H2O)4]3+, sp3
3. [Al(H2O)4]3+, dsp2
4. [Al(H2O)]3+, d2sp3
Match the species given in Column I with properties given in Column II.
| Column I | Column II | ||
| A. | Diborane | 1. | Used as a flux for soldering metals | 
| B. | Quartz | 2. | Crystalline form of silica | 
| C. | Borax | 3. | Banana bonds | 
| D. | Aluminosilicate | 4. | Used as a catalyst in petrochemical industries | 
| A | B | C | D | |
| 1. | 3 | 4 | 1 | 2 | 
| 2. | 1 | 2 | 3 | 4 | 
| 3. | 3 | 2 | 1 | 4 | 
| 4. | 4 | 1 | 3 | 2 | 
Ionization enthalpy () for the elements of Group 13 follows the order.
| 1. | B > Al > Ga > In > Tl | 2. | B < Al < Ga < In < Tl | 
| 3. | B < Al > Ga < In > Tl | 4. | B > Al < Ga > In < Tl | 
Aluminium reacts with concentrated HCl and concentrated NaOH to liberate which of the following gases respectively-
| 1. | \(\mathrm{H}_2 ~\text{and} ~\mathrm{H}_2 \) | 2. | \(\mathrm{O}_2 ~\text{and} ~\mathrm{O}_2 \) | 
| 3. | \(\mathrm{O}_2 ~\text{and} ~\mathrm{H}_2 \) | 4. | \(\mathrm{H}_2 ~\text{and} ~\mathrm{O}_2 \) | 
The correct order of atomic radii of the group 13 elements is-
1. B < Al < In < Ga < Tl
2. B < Al < Ga < In < Tl
3. B < Ga < Al < Tl < In
4. B < Ga < Al < In < Tl
on hydrolysis gives -
1.
2.
3.
4.