Notes on Properties Of Hydrogen | Grade 9 > Science > Some Gases | KULLABS.COM

Properties Of Hydrogen

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The atomic form of hydrogen produced at the time of chemical reaction is known as nascent hydrogen. Nascent means newly born.

Zn + H2SO4 → ZnSO4 + 2 H(nascent)
H + H → H2

Physical properties

  • Hydrogen is a colorless, tasteless and oodorlessgas.
  • It is about insoluble in water.
  • It is the lightest gas.
  • It is neutral to litmus.
  • It liquefies at -235°C and solidifies at -259°C.
  • It is a combustible gas but does not support in burning.

Chemical properties

  • Hydrogen burns in air or in oxygen with a blue flame and it produces water.
    2H2 + O2 → 2 H2O
  • Metals like sodium, potassium and calcium burn in hydrogen forming corresponding forming corresponding unstable metallic hydrides.
    2Na + H2 → 2 NaH (Sodium hydride)
    Ca + H2 → 2 CaH2 (Calcium hydride (Hydrolith))
  • When dry hydrogen is passed over heated oxide of iron, copper, lead, etc. It reduces the metallic oxides to their metals.
    Fe3O4 + 4H2 → 3Fe + 4H2O
    In above reactions, the removal of oxygen from the compound is called reduction and hydrogen which brings about reduction is called reducing agent. But the oxides of calcium, zinc and magnesium are not reduced by hydrogen.
  • Hydrogen reacts with chlorine, bromine, iodine and fluorine (halogens) in various conditions to form acids.
    H2 + Cl2 → 2HCl (hydrochloric acid)
  • Hydrogen combines with nitrogen under 200-900 atmospheric pressure, at 5000 C temperature and in the presence of a catalyst, iron with molybdenum as promoter to give ammonia.
    N2 + 3H2 → 2NH3
  • Hydrogen reacts with burning coal and forms methane.
    2 H2 + C → CH4(methane)

Uses of hydrogen

  • It is used in manufacturing ammonia.
  • Hydrogen gas is used in manufacturing vanaspati ghee.
  • It is used as reducing agent because it reduces metallic oxides into corresponding metals.
  • The liquid form of hydrogen is used as fuel in rockets.




  • The atomic form of hydrogen produced at the time of chemical reaction is known as nascent hydrogen.
  • Hydrogen is a colorless, tasteless and odorless gas.
  • Hydrogen burns in air or in oxygen with a blue flame and it produces water.
  • Hydrogen reacts with nitrogen at suitable conditions to produce ammonia.
.

Very Short Questions

The physical properties of hydrogen gas are as follows:

(1)Hydrogen is colourles, odourless and tasteless gas.
(2) It is lightest gas of the atmosphere.
(3) It is neutral in nature. So, it does not change the color of litmus paper.

The atomic form of hydrogen produced at the time of chemical reaction is known as nascent hydrogen. Nascent means newly born.

Some uses of hydrogen gas are as follows:

(1) Hydrogen gas is used to fill in the balloons.
(2) It is used as fuel in the rocket.
(3) It is used to make hydrogen torch.

Under suitable conditions of temperature and pressure, unsaturated hydrocarbons directly combine with hydrogen gas to form saturated hydrocarbons. This process is known as hydrogenation.

The mixture of carbon monoxide and hydrogen gas is called water gas. It is used in industry as a source of heat.

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  • Which is not a property of Hydrogen gas?

    It is colorless, odorless and tasteless.
    It burns with a Orange flame.
    It is neutral ie it does not change color of litmus paper.
    It is second lightest gas.
  • What color does burning hydrogen give?

    Green
    Yellow
    Orange
    Blue
  • Which is not a use of Hydrogen?

    fill balloons


    cooking fuel in rockets to cook food


    make hydrogen torch


    cutting and welding metals


  • We use hydrogen for

    manufacturing vanaspati ghee
    used as fuel in rockets
    manufacturing ammonia
    All the options are correct
  • You scored /4


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ASK ANY QUESTION ON Properties Of Hydrogen


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Forum Time Replies Report
Shoaib Tabassum

As mixture of CO and H2 is know as water gas and is used for source of heat. CO is poisonous but on the other hand it is also flammable. Is it possible to use as automobile fuel?


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melina sakya

as hydrogen is already present in water, i.e. water consists of 2 hydrogen and 1 oxygen, why is it insoluble in water ?


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