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प्रश्न
A solid element X has four electrons in the outermost shell of its atom. An allotrope Y of this element is used as a dry lubricant in machinery and also in making pencil leads.
(a) What is element X?
(b) Name the allotrope Y.
(c) State whether allotrope Y is a good conductor or non-conductor of electricity.
(d) Name one use of allotrope Y (other than lubrication and pencil leads)
(e) Name two other allotropes of element X.
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उत्तर
(a) The solid element 'X' is carbon, which has four electrons in the outermost shell of its atom.
(b) Graphite is the allotrope 'Y' of carbon which is used as a dry lubricant in machinery, and al in making pencil leads.
(c) Graphite (Y) is a good conductor of electricity because of the presence of free electrons in its crystal.
(d) Graphite (Y) is used in making carbon electrodes or graphite electrodes in dry cells and electric arcs.
(e) Diamond and buckminsterfullerene are the two other allotropes of carbon.
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संबंधित प्रश्न
List three characteristic properties of covalent compounds.
An element L consists of molecules.
What type of bonding is present in the particles that make up L?
Fill in the blank in the following sentence:
The number of single covalent bonds in C2H2 molecule are ...........
How buckminsterfullerene is it related to diamond and graphite?
How will you find out which of the water soluble compound A or B is ionic?
Using electron-dot diagrams which show only the outermost shell electrons, show how a molecule of oxygen, O2, is formed from two oxygen atoms. What name is given to this type of bonding? (At. No. of oxygen = 8)
Define a covalent bond.
State the type of bonding in the following molecule.
Hydroxyl ion
Draw an electron dot diagram for the formation of the following. State the type of bonding present in them.
Hydroxyl ion
Give two example in following case:
Solid covalent compounds
Give two example in following case:
Gaseous polar compounds
Distinguish between ionic and covalent compounds under the following properties:
(i) Strength of forces between constituent elements
(ii) Solubility of compounds in water
(iii) Electrical conduction in substances
(a) Compound X consists of molecules.
Choose the letter corresponding to the correct answer from the choices (a), (b), (c) and (d) given below
X is likely to have a :
Draw an electron dot diagram to show the formation of the following compound.
Methane
Name two carbon compounds used in day-to-day life.
Write an Explanation.
Alkene
Complete the following activity.
Write the names of the hydrocarbons for the following structural formula.
(isobutylene, cyclohexane, propene, cyclohexene, cyclopentane, benzene, propyne, isobutane, propane)
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What is a covalent bond?
In covalent compounds, the bond is formed due to ______ of electrons.
