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प्रश्न
Explain why, graphite can be used as a lubricant but diamond cannot.
उत्तर
Because of its softness and non-volatile nature, graphite is used as a lubricant in the fast moving parts of a machinery. It is used for lubricating the parts of machinery which operate at high temperatures. Diamond, on the other hand, is an extremely hard substance; therefore, it cannot be used as a lubricant.
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संबंधित प्रश्न
Explain the nature of the covalent bond using the bond formation in CH3Cl.
What type of bonds are present in methane (CH4) and sodium chloride (NaCl)?
What type of bonds are present in CH4 molecule? Draw their electron-dot structures.
What is a covalent bond?
What type of bond exist in CCl4?
What type of chemical bonds are formed by carbon? Why?
State one test by which sodium chloride can be distinguished from sugar.
State any two uses of diamond.
Why are covalent compounds generally poor conductors of electricity?
The atomic numbers of four elements P, Q, R and S are 6, 10, 12 and 17 respectively. Which two elements can combine to form a covalent compound?
(a) P and R
(b) Q and S
(c) P and S
(d) R and S
Give the formulae of the chlorides of the elements X and Y having atomic numbers of 3 and 6 respectively. Will the properties of the two chlorides be similar or different? Explain your answer.
Explain the following:
Non-polar covalent compounds are insoluble in water.
What is the term defined below?
A bond formed by a shared pair of electrons, each bonding atom contributing one electron to the pair.
An element L consists of molecules.
Why L is heated with iron metal, it forms a compound FeL. What chemical term would you use to describe the change undergone by L?
Draw an electron dot diagram to show the formation of the following compound.
Methane
Give an example of the covalent bond formed by
(i) Similar atoms (ii) Dissimilar atoms
Name greenish-yellow gas which also bleaches.
Complete the following activity.
Write the names of the hydrocarbons for the following structural formula.
(isobutylene, cyclohexane, propene, cyclohexene, cyclopentane, benzene, propyne, isobutane, propane)
| \[\begin{array}{cc}\ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\\ |\phantom{....}|\phantom{....}|\\\ce{H - C - C - C - H}\\ |\phantom{....}|\phantom{....}|\\\ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H} \end{array}\] |
______ is an example of a covalent compound having a high melting point.
The electron dot structure of chlorine molecule is:
