Tag: hydrogen

Questions Related to hydrogen

In which of the following reactions hydrogen gas is liberated ?

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

  1. $C{H _3}COOH + Na$

  2. $C{H _3}COOH + NaHC{O _3}$

  3. $C{H _3}COOH + NaOH$

  4. $C{H _3}COOH + {H _2}O.$

Show answer
Correct Option: C

Brass gets discoloured in air because of the presence of which of the following gases in air  ?

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

  1.  Hydrogen sulphide

  2.  Oxygen

  3.  Nitrogen

  4. Carbon dioxide

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Correct Option: A
Explanation:

 Hydrogen sulphide

Metals like .......... , ........... and .......... give $H _2$ with steam.

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

  1. iron

  2. magnesium

  3. aluminium

  4. sodium

  5. calcium

  6. none of the above

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Correct Option: A,B,C
Explanation:

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


Magnesium ribbon reacts with steam to give Magnesium oxide and Hydrogen gas.

$Mg$ $+$ $H _2O$ $=$ $MgO$ $+$ $H _2$

Aluminium reacts with steam to give Aluminium Oxide and Hydrogen gas. But the reaction takes place very slowly, as a layer of Aluminium Oxide forms on the metal.

$2Al$ $+$ $3H _2O$ $=$ $Al _2O _3$ $+$ $3H _2$
Iron does not react with cold water. It reacts with steam to form Ferric Oxide and hydrogen gas.

$3Fe$ $+$ $4H _2O$ $=$ $Fe _3O _4$ $+$ $4H _2$
Thus, options A, B  and C are correct.

Sodium ________ reacts vigorously with cold water.

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

  1. metal

  2. amalgam

  3. in the molten state

  4. none of the above

Show answer
Correct Option: A
Explanation:

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


$2 Na(s) + 2H _2O \rightarrow 2 NaOH(aq) + H _2(g)$

At $298 \, K$ , assuming ideal behaviour, the average kinetic energy of a deuterium molecule is :

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

  1. Two times that of a hydrogen molecule

  2. Four times that of a hydrogen molecule

  3. Half of that of a hydrogen molecule

  4. Same as that of a hydrogen molecule

Show answer
Correct Option: D
Explanation:

Average Kinetic Energy depends only on temperature

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

Under suitable conditions, the following reaction:
Metal+Water $\xrightarrow [  ]{ Heat } $ Oxide or hydroxide of metal + Hydrogen 

may take place? Find which of the following metals, does not react in this way.

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

  1. Sodium

  2. Copper

  3. Iron

  4. Magnesium

Show answer
Correct Option: B
Explanation:

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

Hydrogen gas is manufactured by:

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

  1. Bosch's process

  2. Haber's process

  3. Ostwald process

  4. Birkeland-Eyde process

Show answer
Correct Option: A
Explanation:

Among the given option, the Bosch process is correct.

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

The process of producing syngas from coal is called ______________.

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

  1. coal cracking

  2. coal gasification

  3. coal pyrolysis

  4. both $A$ and $B$

Show answer
Correct Option: B
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.

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 __________.

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

  1. water gas

  2. syngas

  3. producer gas

  4. industrial gas

Show answer
Correct Option: A,B
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.

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

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

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

  1. combustion

  2. disproportionate

  3. coal gasification

  4. water-gas shift

Show answer
Correct Option: D
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):

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