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Multiple choice chemistry study of the first element - hydrogen occurrence of hydrogen introduction to hydrogen hydrogen

Hydrogen gas is manufactured by:

  1. Bosch's process

  2. Haber's process

  3. Ostwald process

  4. Birkeland-Eyde process
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Among the given option, the Bosch process is correct.

It is the commercial preparation of dihydrogen from water gas.
$C+{ H } _{ 2 }O\longrightarrow CO+{ H } _{ 2 }$
$CO+{ H } _{ 2 }O \xrightarrow { 773K }  { CO } _{ 2 }+{ H } _{ 2 }O$

Multiple choice chemistry study of the first element - hydrogen occurrence of hydrogen introduction to hydrogen hydrogen

The process of producing syngas from coal is called ______________.

  1. coal cracking

  2. coal gasification

  3. coal pyrolysis
  4. both $A$ and $B$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

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.

Multiple choice chemistry study of the first element - hydrogen occurrence of hydrogen introduction to hydrogen hydrogen

Dihydrogen can be prepared on a commercial scale by different methods. In its preparation by the action of steam on hydrocarbons, a mixture of $CO$ and $H 2$ gas is formed. It is known as __________.

  1. water gas

  2. syngas

  3. producer gas

  4. industrial gas
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation

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.

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

Multiple choice chemistry study of the first element - hydrogen occurrence of hydrogen introduction to hydrogen hydrogen

Following reaction is called __________ reaction.
$CO (g)\ +\ H _2O (g) \xrightarrow [catalyst]{673} CO _2(g)\ +\ H _2(g)$

  1. combustion

  2. disproportionate

  3. coal gasification

  4. water-gas shift
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

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):

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

Multiple choice chemistry study of the first element - hydrogen occurrence of hydrogen introduction to hydrogen hydrogen

Which of the following reactions is an example of a use of water gas in the synthesis of other compounds?

  1. $CH _4(g) +\ H _2O(g) \xrightarrow[Ni]{1270 K} CO(g) +\ 3H _2(g)$
  2. $CO(g) +\ H _2O(g) \xrightarrow[Catalyst]{673 K} CO _2(g) +\ H _2(g)$
  3. $CnH _{2n+2}(g) +\ nH _2O(g) \xrightarrow[Ni]{1270 K} nCO(g) +\ (2n+1)H _2(g)$
  4. $CO(g) +\ 2H _2(g) \xrightarrow[Catalyst]{Cobalt} CH _3OH(l)$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

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%): 

$\\ CO+2{ H } _{ 2 }→C{ H } _{ 3 }OH$

Multiple choice chemistry study of the first element - hydrogen occurrence of hydrogen introduction to hydrogen hydrogen

Water gas is also called as syngas

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

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.

Multiple choice chemistry study of the first element - hydrogen occurrence of hydrogen introduction to hydrogen hydrogen

Which method is used to remove $CO$ from syngas($CO+H _2$) during Syngas Bosch process?

  1. Oxidation by using $KMnO _4$

  2. Oxidation by mixing steam
  3. Oxidation by using $K _2Cr _2O _7$

  4. All of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

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

$CO + H _2O(steam) \longrightarrow CO _2 + H _2$

Multiple choice chemistry study of the first element - hydrogen occurrence of hydrogen introduction to hydrogen hydrogen

The formation of atomic hydrogen is favored at:

  1. high temperature and low pressure

  2. low pressure and high temperature

  3. high temperature and high pressure

  4. low temperature and low pressure
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

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).)

Multiple choice chemistry study of the first element - hydrogen occurrence of hydrogen introduction to hydrogen hydrogen

Water gas is mixed with steam and the mixture is passed over heated $Fe _{2}O _{3}$ in presence of $Cr _{2}O _{3}.$
The mixture when passed in water dissolves $CO _{2}$ and dihydro gen left undissolved is collected. This method of preparation of hydrogen gas is known as:

  1. Bosch process

  2. Lane process

  3. Kellner process

  4. Hall process
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

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


In Bosch's process, water gas (i.e. $CO+H _2$ ) is mixed with twice of its volume of steam in presence of catalysts $Fe _2O _3$ and $Cr _2O _3$ or $ThO _2$ where $Cr _2O _3$ acts as promoter. It gives the products $CO _2$ and $H _2$. Now, $CO _2$ is dissolved in water & removed leaving $H _2$ behind which is undissolved.