Advertisements
Advertisements
Question
Explain why, diamond is hard while graphite is soft (though both are made of carbon atoms).
Solution
Even if diamond and graphite are made up of carbon, the former is extremely hard while the latter is soft. Diamond is hard because of the strong covalent bond between its carbon atoms forming a regular tetrahedron which is hard to break. Graphite, on the other hand, consists of flat hexagonal ring forming layers of carbon atoms. The various layers of the carbon atoms are far apart from each other; hence, the covalent bond cannot exist. The layers are held together by weak van der Waals forces, thereby allowing them to slide over each other. Due to this layered structure, graphite is softer than diamond.
APPEARS IN
RELATED QUESTIONS
Write the number of covalent bonds in the molecule of butane, C4H10.
Name the type of bonds formed in ionic compounds and in the compounds formed by carbon.
State the reason to explain why covalent compounds "are bad conductors of electricity".
Choose the most appropriate answer from the following list of oxides which fit the description.
A covalent oxide of a metalloid.
Draw the electron-dot structure of HCl compound and state the type of bonding.
Explain why, diamond has a high melting point.
A hydrocarbon having one double bond has 100 carbon atoms in its molecule. The number of hydrogen atoms in its molecule will be
(a) 200
(b) 198
(c) 202
(d) 196
Define a covalent bond.
Draw an electron dot diagram for the formation of the following. State the type of bonding present in them.
Hydroxyl ion
Explain the following term with example.
Hetero atom in a carbon compound
Choose and write the correct option.
Which type of carbon-carbon bonds are present in Vanaspati ghee?
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.
Potassium (Atomic No. 19) and chlorine (Atomic No. 17) react to form a compound. On the basis of electronic concept, explain
(i) oxidation
(ii) reduction
(iii)oxidising agent
(iv)reducing agent
Write the molecular formula of the given compound.
Acetic acid
List two differences between the properties exhibited by covalent compounds and ionic compounds.
Give an example for each of the following statement.
Formation of coordinate covalent bond between NH3 ➝ BF3 molecules
Which of the following is the formula of Butanoic acid?
Molecular reactions are ______ in the covalent compound.
Statement (A): Covalent compounds are bad conductors of electricity.
Reason (B): Covalent compounds contain charged particles (ions)
Name the following:
\[\ce{CH3 - CH2CH = CH2}\]