Hydrogen sulphide

Metals which react with steam to give $H _2$ gas are Iron, Magnesium and Aluminium.

Sodium metal is an extremely reactive metal. When sodium metal comes into contact with water, it displaces hydrogen gas as follows:

Average Kinetic Energy depends only on temperature

$\displaystyle (KE) _{avg} = \frac {3kT} {2} $ per molecule

Because $Cu$ is placed below ${ H } _{ 2 }$ in reactivity series, hence cannot displace ${ H } _{ 2 }$. Hence reaction does not occur.

Among the given option, the Bosch process is correct.

Coal gasification is the process of producing syngas–a mixture consisting primarily of methane ($C{ H } _{ 4 }$), carbon monoxide (CO), hydrogen (${ H } _{ 2 }$), carbon dioxide ($C{ O } _{ 2 }$) and water vapor (${ H } _{ 2 }O$)–from coal and water, air and/or oxygen.

Steam reforming is a method for producing hydrogen, carbon monoxide, or other useful products from hydrocarbon fuels such as natural gas. This is achieved in a processing device called a reformer which reacts steam at high temperature with the fossil fuel.

Steam reforming of natural gas - sometimes referred to as steam methane reforming (SMR) - is the most common method of producing commercial bulk hydrogen. Hydrogen is used in the industrial synthesis of ammonia and other chemicals. At high temperatures (700 – 1100 °C) and in the presence of a metal-based catalyst (nickel), steam reacts with methane to yield carbon monoxide and hydrogen.

$C{ H } _{ 4 }+{ H } _{ 2 }O\leftrightharpoons CO+3{ H } _{ 2 }$

The water-gas shift reaction (WGSR) describes the reaction of carbon monoxide and water vapor to form carbon dioxide and hydrogen (the mixture of carbon monoxide and hydrogen is known as water gas):

$CO+{ H } _{ 2 }O\rightleftharpoons C{ O } _{ 2 }+{ H } _{ 2 }$

Carbon monoxide and hydrogen react over a catalyst to produce methanol. Today, the most widely used catalyst is a mixture of copper and zinc oxides, supported on alumina, as first used by ICI in 1966. At 5–10 MPa (50–100 atm) and 250 °C (482 °F), the reaction is characterized by high selectivity (>99.8%): 

$\\ CO+2{ H } _{ 2 }→C{ H } _{ 3 }OH$

Water gas is actually an older terminology. From the view point of composition, they both have the same components: Hydrogen and carbon monoxide, with or without some amount of carbon dioxide. However, what is different is the way they are produced. Water gas was usually produced by passing steam over red hot coke. On the other hand syngas is mainly produced industrially by steam reforming of natural gas that involves catalytic decomposition of methane in steam to give the resultant mixture along with the traditional coal gasification and various other methods.

 This process of removal of $CO$ from syngas uses the water-gas shift reaction:

 This process of removal of $CO$ from syngas uses the water-gas shift reaction:

The formation of atomic hydrogen is favored at high temperature and low pressure. The enthalpy of formation of atomic hydrogen is 217.97 kJ. This is the enthalpy change when a mole of atomic hydrogen is formed by dissociating 1/2 mole of molecular hydrogen (the more stable state of the element).)

For the commercial preparation of dihydrogen, Bosch process is used.

Sodium peroxide $\left( { Na } _{ 2 }{ O } _{ 2 } \right) $, when it reacts with sulphuric acid $\left( { H } _{ 2 }{ SO } _{ 4 } \right) $, it leads to the formation of sodium sulphate $\left( { Na } _{ 2 }{ SO } _{ 4 } \right) $ with hydrogen peroxide $\left( { H } _{ 2 }{ O } _{ 2 } \right) $.