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Metals

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On the basis of certain basic properties, all the elements have been divided into two classes: metals and non-metals. 80% of the total elements (known till now) are metals. Metals are the good conductor of heat and electricity, they are malleable and ductile. Most of the metals are found in combined state.Metals are strong and are useful for making tools, buildings, bridges and other structures where strength is important. The most abundant metal on the earth is iron.The tallest free-standing structures in the world are made of metals, primarily the alloy steel. They include the Dubai skyscraper Burj Kalifa, the Tokyo television tower Skytree, and the Shanghai Tower skyscraper. Some of the examples of metals are copper, gold, iron, aluminium, etc.

Properties of metals

Physical properties

  • State: Most of the metals are solid at ordinary temperature except mercury.
  • Hardness: Most of the metals are generally hard in nature.
  • Lustre: Metals possess metallic lustre when they are freshly cut.
  • Density: Metals have relatively high densities except lithium, sodium and potassium.
  • Malleability: Metals can be beaten into a thin plate, such property is called malleability.
  • Ductility: The property of metal being made into wires is called ductility and the metal is called ductile.
  • Conductivity: Metals are generally good conductors of heat and electricity.
  • Melting and boiling point of metal: The melting and boiling point of metals are generally high due to their high density and hardness.
  • Electric charge: Metals are electropositive elements which give cations when ionized. In aqueous solutions, metallic salts undergo ionization and produce metallic ions.

Chemical properties

  • Reaction with oxygen: When metal is treated with oxygen on heating they react together to give basic oxides.
    4Na + O2→ 2Na2O
  • Reaction with Hydrogen: Metals like sodium, potassium, and calcium burn in hydrogen and forms corresponding halides.
    2Na + H2→ 2NaH (sodium hydride)
    2K + H2→ 2KH (potassium hydride)
  • Reaction with acids: Most of the reactive metals like sodium, potassium and calcium react with dilute acid to form salts and hydrogen gas.
    Zn + 2HCl→ ZnCl2 + H2



  • Most of the metals are solid at ordinary temperature except mercury.
  • Most of the metals are generally hard in nature.
  • Metals possess metallic luster when they are freshly cut.
  • Metals have relatively high densities except lithium, sodium and potassium.
  • When metal are treated with oxygen on heating they react together to give basic oxides.
  • Metals like sodium, potassium, and calcium burn in hydrogen and forms corresponding halides.
  • Most of the reactive metals like sodium, potassium and calcium react with dilute acid to form salts and hydrogen gas.
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Very Short Questions

Metals are those electropositive elements which are good conductor of heat and electricity. For example, gold, platinum, iron, etc.

Non-metals are those electropositive elements which are bad conductor of heat and electricity. For example, oxygen, nitrogen, sulphur, iodine, etc.

The physical properties of metals are: (i) Metals are good conductor of heat and electricity. (ii) They are ductile in nature. (iii) They can be converted into thin sheet after hammering. Thus, we can say that they are malleable in nature.

The melting point and boiling point of silver are 960 degree C and 1955 degree C respectively.

The property of metal being made into wires is called ductility.

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  • Which is false?

    Metalloid have characteristic of both metals and non-metals
    There are only 112 elements known till now
    Metals are solid
    Non-metals can be can be solid, liquid or gas
  • Which is an example of metal?

    Beryllium
    Chlorine
    Fluorine
    Na2O
  • Which is not a property of metals?

    Ductile
    Conductance of heat
    Malleable
    Lush
  • Which metal is liquid at room temperature?

    Cobalt
    Calcium
    Iron
    Cesium
  • Which metal is not hard?

    Iron
    Lithium
    Magnesium
    Aluminum
  • Which metal has low boiling point?

    Magnesium
    Iron
    Aluminum
    Mercury
  • What is false about metals?

    They are sonorous in nature
    They make homogenous mixture with other metals called alloy
    They are good reducing agents which means they easily combine with hydrogen
    They have high density
  • What is false about metals?

    They are good oxidizing group
    They are non-sonorous in nature
    They do not produce hydrogen gas with acids
    Their oxides are basic in nature
  • Pure gold is ___ carat

    20
    24
    26
    22
  • Why isn't pure gold used to make jewelry?

    Pure gold gives skin rash
    it is very expensive
    It is very hard for handling
    It is very soft for handling
  • 22 carat gold ____ than 24 carat gold?

    is stronger
    is less lustrous
    has more melting point
    is less Ductile
  • Rold gold is composed of

    Zinc and copper
    Chromium and iron
    Zinc and iron
    Copper and Aluminum
  • What happens during rusting?

    Iron becomes harder
    Iron becomes thin
    Iron becomes brittle
    Iron becomes lighter
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Difference between metal and nonmetals chemically

Difference between metal and nonmetals chemically


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Bineet

Why metals have high density?


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sodium

difference between metal and non metal


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