Hydrogen

Methane reacts with steam at 1273 K in the presence of nickel catalyst to form :

1. CO and H2
2. CO and H2O
3. CO2 and H2
4. CO2 and H2O

Which of the following statements are NOT correct? Choose the most appropriate answer from the options given below:

1. B, D only
2. D, E only
3. A, B, C only
4. B, C, D, E only

Match List-I with List-II. Choose the correct answer from the options given below:

1. (a)-(iv), (b)-(i), (c)-(ii), (d)-(iii)
2. (a)-(iii), (b)-(i), (c)-(ii), (d)-(iv)
3. (a)-(i), (b)-(ii), (c)-(iv), (d)-(iii)
4. (a)-(ii), (b)-(iii), (c)-(iv), (d)-(i)

The element used for welding metals with high melting points is

1. He
2. Cl2
3. H2
4. Ne

Tritium, a radioactive isotope of hydrogen, emits which of the following particles?

1. Neutron (n)
2. Beta ( -)
3. Alpha ( )
4. Gamma ( )

Match the following and identify the correct option.

1. (a)-(iii), (b)-(ii), (c)-(i), (d)-(iv)
2. (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)
3. (a)-(i), (b)-(iii), (c)-(ii), (d)-(iv)
4. (a)-(iii), (b)-(i), (c)-(ii), (d)-(iv)

The method used to remove temporary hardness of water is :

1. Ion-exchange method
2. Synthetic resins method
3. Calgon’s method
4. Clark’s method

Among CaH2, BeH2, BaH2, the order of ionic character is

1. BeH2 < CaH2 < BaH2
2. CaH2 < BeH2 < BaH2
3. BeH2 < BaH2 < CaH2
4. BaH2 < BeH2 < CaH2

Which of the following statements about hydrogen is incorrect?

1. Hydronium ion, H3O+ exists freely in solution.
2. Dihydrogen does not act as a reducing agent.
3. Hydrogen has three isotopes of which tritium is the most common.
4. Hydrogen never acts as cation in ionic salts.

(I) H2O2 + O3 H2O + 2O2 (II) H2O2 + Ag2O 2Ag + H2O + O2 Role of hydrogen peroxide in the above reactions is respectively

1. oxidizing in (I) and reducing in (II)
2. reducing in (I) and oxidizing in (II)
3. reducing in (I) and (II)
4. oxidizing in (I) and (II)