$A$ is an element having four electrons in its outermost orbit. An allotrope $B$ of this element is used as a dry lubricant in machinery and in pencil leads. So :
(a) Write the name of element $A$ and its allotropes.
(b) State whether $B$ is a good conductor or non-conductor of electricity?

Open in App

Solution

(a) The element $A$ is carbon and its allotropes are diamond, graphite and fullerene. Graphite is used as a dry lubricant in machinery and in pencil leads.
(b) Graphite has delocalised molecular orbitals and the electrons are free to move in these delocalised molecular orbitals. Hence, graphite is a good conductor of electricity.

Suggest Corrections

Similar questions

Q. 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.

Q. The solid element A exhibits the property of catenation. It is also present in the form of a gas B in the air which is utilised by plants in photosynthesis. An allotrope C of this element is used in glass cutters.
(a) What is element A?
(b) What is the gas B?
(c) Name the allotrope C.
(d) State another use of allotrope C (other than in glass cutters).
(e) Name another allotrope of element A which exists as spherical molecules.
(f) Name a yet another allotrope of element A which conduct electricity.

Q. An element E exists in three allotropic forms A, B and C. In allotrope A, the atoms of element E are joined to form spherical molecules. In allotrope B, each atom of element E is surrounded by three other E atoms to form a sheet-like structure. In allotrope C, each atom of element E is surrounded by four other E atoms to form a rigid structure.
(a) Name the element E.
(b) What is allotrope A?
(c) What is allotrope B?
(d) What is allotrope C?
(e) Which allotrope is used in making jewellery?
(f) Which allotrope is used in making the electrode of a dry cell?

Q. Graphite is known for its use in pencils, where it is commonly called lead. Graphite occurs in metamorphic rocks as a result of the reduction of sedimentary compounds during metamorphism. Consider the following statements regarding graphite
(a) It is an allotrope of carbon.
(b) It is good conductor of heat and electricity.
(c) It can be artificially produced.
Of these statements

An element 'M' has atomic number 11. [5 MARKS]
1. Write its electronic configuration.
2. State the group to which 'M' belongs.
3. Is 'M' a metal or a non-metal?
4. Write the formula of its chloride.
5. Name at least four elements present in this group.

Join BYJU'S Learning Program

A is an element having four electrons in its outermost orbit. An allotrope B of this element is used as a dry lubricant in machinery and in pencil leads. So :(a) Write the name of element A and its allotropes.(b) State whether B is a good conductor or non-conductor of electricity?

$A$ is an element having four electrons in its outermost orbit. An allotrope $B$ of this element is used as a dry lubricant in machinery and in pencil leads. So :
(a) Write the name of element $A$ and its allotropes.
(b) State whether $B$ is a good conductor or non-conductor of electricity?