Tag: hydrogen

Quizzes (9) Questions (42)

Questions Related to hydrogen

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.

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

hydrogen peroxid  is not produced by the reaction :-

  1. $Na _2O _2 + dil.H _2SO _4$
  2. $Mg + H _2O$
  3. $BaO _2 + HCl$
  4. $BaO _2 + H _3PO _4$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

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) $.

${ Na } _{ 2 }{ O } _{ 2 }+{ H } _{ 2 }{ SO } _{ 4 }\longrightarrow { Na } _{ 2 }{ SO } _{ 4 }+{ H } _{ 2 }{ O } _{ 2 }$
Also, $Mg+{ H } _{ 2 }O\longrightarrow { Mg\left( OH \right)  } _{ 2 }$
${ BaO } _{ 2 }+HCl\longrightarrow Ba{ Cl } _{ 2 }+{ H } _{ 2 }{ O } _{ 2 }$
${ BaO } _{ 2 }+{ H } _{ 3 }{ PO } _{ 4 }\longrightarrow { Ba } _{ 3 }{ \left( { PO } _{ 4 } \right)  } _{ 2 }+{ H } _{ 2 }{ O } _{ 2 }$
Thus, in all of the above reactions, hydrogen peroxide $\left( { H } _{ 2 }{ O } _{ 2 } \right) $ is formed.

Multiple choice hydrides hydrogen and its compounds hydrogen chemistry

$Ca{H _2}$ is an example of :

  1. Ionic hydride

  2. Covelent hydride

  3. Metallic hydride

  4. Polymeric hydride
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Calcium hydride (CaH2) is formed by an alkaline earth metal and hydrogen, resulting in an ionic bond between the metal cation and the hydride anion.

Multiple choice hydrides hydrogen and its compounds hydrogen chemistry

Which of the following pair behaves strong and weak base hydride :


$NH _3, PH _3, AsH _3, SbH _3, BiH _3$

  1. $NH _3, PH _3$
  2. $NH _3, BiH _3$
  3. $PH _3, BiH _3$
  4. $BiH _3, AsH _3$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In the group 15 hydrides, basicity decreases down the group as the lone pair becomes more diffuse and less available for donation. Thus, NH3 is the strongest base and BiH3 is the weakest.