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प्रश्न
Explain why, diamond can be used in rock drilling equipment but graphite cannot.
उत्तर
As diamond is extremely hard, it can be used to cut and grind other hard materials or metals. Hence, it is used in rock-drilling equipment to drill holes in the rocky layers of the Earth. Graphite being soft cannot be used to cut or grind.
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संबंधित प्रश्न
What would be the electron dot structure of carbon dioxide which has the formula CO2?
Buckminsterfullerene is spherical molecule in which 60 carbon atoms are arranged in interlocking hexagonal and pentagonal rings of carbon atoms.
How many pentagons of carbon atoms are present in one molecule of buckminsterfullerene?
What is a covalent bond?
A covalent molecule having a double bond between its atoms is:
(a) Hydrogen
(b) Oxygen
(c) water
(d) ammonia
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.
Draw all possible structural formulae of compound from their molecular formula given below.
C3H8
Draw all possile structural formulae of compound from their molecular formula given below.
C4H10
Explain the Structural isomerism term with example.
Fill in the blank with correct word from the bracket.
Melting and boiling points of covalent compounds are generally ______ (low, high).
Fill in the blank from the choice given in bracket.
The compound that does not have a lone pair of electrons is ___________. (Water, Ammonia, carbon tetrachloride)
Explain the following:
Water is a polar covalent molecule.
Element A has 2 electrons in its M shell. Element B has atomic number 7.
If the compound formed between A and B is melted and an electric current is passed through the molten compound, the element A will be obtained at the ______ and B at the ______ of the electrolytic cell.
What is the difference between a polar covalent compound and a non-polar covalent compound?
Number of valence electrons in a carbon atom is _______.
Write an Explanation.
Alkane
Write a short note.
Characteristics of carbon
Give an example for each of the following statement.
Formation of coordinate covalent bond between NH3 ➝ BF3 molecules
Consider the coordination compound, K2[Cu(CN)4]. A coordinate covalent bond exists between:
Acetic acid was added to a solid X kept in a test tube. A colourless, odourless gas Y was evolved. The gas was passed through lime water, which turned milky. It was concluded that ______.
Statement (A): Covalent compounds are bad conductors of electricity.
Reason (B): Covalent compounds contain charged particles (ions)
