Metallic hydrides are useful for hydrogen storage because :
1. Metallic hydrides are oxygen-rich.
2. Metallic hydrides are oxygen-deficient.
3. Metallic hydrides are hydrogen-rich.
4. Metallic hydrides are hydrogen-deficient.
Atomic hydrogen or oxy-hydrogen torch is used for cutting and welding purposes because:
1. | Atomic hydrogen converts into molecular hydrogen and generates a large amount of energy. |
2. | Atomic hydrogen converts into molecular hydrogen and generates a low amount of energy. |
3. | Molecular hydrogen converts into atomic hydrogen and generates a large amount of energy. |
4. | Molecular hydrogen converts into atomic hydrogen and generates a low amount of energy. |
The correct order of hydrogen bonding among , H2O and HF, is
1. HF > >
2. > HF >
3. HF > >
4. > HF >
CO2 is used as a fire extinguisher because -
1. has high lattice energy.
2. will be effective in isolating the burning surface from dihydrogen and dioxygen.
3. is lighter than dioxygen.
4. is lighter than dihydrogen.
The term ’auto-protolysis’ of water means :
1. | Physical reaction in which two water molecules react to produce a hydroxide ion (OH–) and a hydronium ion (). |
2. | Chemical reaction in which five water molecules react to produce a hydroxide ion (OH–) and a hydronium ion (). |
3. | Chemical reaction in which two water molecules react to produce a hydroxide ion (OH–) and a hydronium ion (). |
4. | Chemical reaction in which two water molecules react to produce three hydroxide ions (OH–) |
The correct statement about the reaction of water with fluorine is:
1. | O is reduced from 0 to -1 oxidation state, whereas F is oxidized from –2 to 0 |
2. | F is reduced from 0 to -1 oxidation state, whereas O is oxidized from –2 to 0 |
3. | F is reduced from 0 to –2 oxidation state, whereas O is oxidized from – 2 to -1 |
4. | O is reduced from 0 to –2 oxidation state, whereas F is oxidized from –3 to 0 |
The structure of the common form of ice is :
1. | Each hydrogen atom is surrounded tetrahedrally by four other oxygen atoms at a distance of 540 pm. |
2. | Each hydrogen atom is surrounded tetrahedrally by four other oxygen atoms at a distance of 276 pm. |
3. | Each oxygen atom is surrounded tetrahedrally by four other oxygen atoms at a distance of 276 pm. |
4. | Each oxygen atom is surrounded tetrahedrally by four other oxygen atoms at a distance of 540 pm. |
The softening of hard water by synthetic ion-exchange resins is based on -
1. Increasing the lattice energy.
2. Physical separation.
3. Lowering the activation energy.
4. Exchange of cations and anions.
Water acts as a base in -
1. Reaction with
2. Reaction with
3. Reaction with NaOH
4. All of the above
‘Demineralised’ water can be obtained by :
1. | Passing water successively through an anion exchange (in the K+ form) and cation exchange (in the Mn- form) resin |
2. | Passing water successively through a cation exchange (in the H+ form) and an anion exchange (in the OH- form) resin |
3. | Passing water successively through an anion exchange (in the O+ form) and cation exchange (in the OH- form) resin |
4. | Passing water successively through a cation exchange (in the OH- form) and an anion exchange (in the H+ form) resin |