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Question
‘A’ is an element having four electrons in its outermost orbit. An allotropes ‘B’ of this element is used as a dry lubricant in machinery and in pencil leads. So:
i. Write the name of element ‘A’ and its allotropes.
ii. State whether ‘B’ is a good conductor or non-conductor of electricity?
Solution
(i) The name of the element 'A' is carbon. The name of its allotrope is graphite.
(ii) The allotrope 'B', i.e. graphite, is a good conductor of electricity.
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|\phantom{..}\\
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\ce{CH3}\phantom{.....}\ce{CH3}\phantom{.........}\ce{CH3}\phantom{..}\ce{CH3}\phantom{..........}\\
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\[\begin{array}{cc}
\phantom{}\ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\phantom{...}\ce{H}\phantom{}\\
\phantom{}|\phantom{....}|\phantom{....}|\phantom{....}|\phantom{....}|\phantom{....}|\phantom{....}|\phantom{}\\
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\[\begin{array}{cc} \phantom{........}\ce{H}\phantom{.....}\ce{O}\\ \phantom{.......}|\phantom{....}//\\ \ce{H - C - C}\\ \phantom{......}|\phantom{.....}\backslash\\ \phantom{...........}\ce{H}\phantom{.....}\ce{O - H} \end{array}\] |
\[\begin{array}{cc}
|
\[\begin{array}{cc} \ce{H}\phantom{...}\ce{H}\phantom{....}\\ |\phantom{....}|\phantom{....}\\ \ce{H - C - C - O - H}\\ |\phantom{....}|\phantom{.....}\\ \ce{H}\phantom{....}\ce{H}\phantom{.....} \end{array}\] |
