Question

draw an electron dot diagram to show the formation of each 1.Alkane 2.Alkene​

Answer 1

We need to draw the electron dot diagram to show the formation of , (1) Alkane and (2) Alkene . We know that , the first member of Alkane group is Methane with a Molecular formula of CH₄ . And the first member of Alkene is Ethene , with a molecular formula of C₂H₄ .

$\underline{\underline{\blacksquare\pink{\textsf{ Lewis dot Structure of Alkane:- }}}}$

• The first member of this group is Methane . Alkanes have a general formula of $\sf C_nH_{2n+2}$ , and they are Saturated hydrocarbons .

• The Methane has one C atom and 4 H atom. The valency of C is 4 , and that of H is 1 . So , each carbon atom forms a single covalent bond with the four atoms of Hydrogen. For the Lewis dot structure refer to attachment.

$\setlength{\unitlength}{1 cm}\begin{picture}(12,8)\put(2,2){\sf C}\put(3,2){\sf H }\put(1,2){\sf H }\put(2,3){\sf H }\put(2,1){\sf H } \put(1.29,2){ \times\odot }\put(2.3,2){ \odot\times }\put(2,1.6){ \odot }\put(2,1.3){ \times }\put(2,2.7){ \times }\put(2,2.4){ \odot }\end{picture}$

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$\underline{\underline{\blacksquare\pink{\textsf{ Lewis dot Structure of Alkene:- }}}}$

• The the first member of this group is ethene . Akenes have general formula of $\sf C_nH_{2n}$ , and they are Unsaturated hydrocarbons .

• Ethene has 2 carbon atoms and 4 hydrogen atoms. So the two carbon atoms form double bond with each other and each carbon atoms forms a single bond with 2 hydrogen atoms. For the Lewis dot structure refer to attachment.

$\setlength{\unitlength}{1 cm}\begin{picture}(12,8)\put(3,3){\sf C \:\: :: \:\:C } \put(3,4){\sf H }\put(3,2){\sf H }\put(4,4){\sf H }\put(4,2){\sf H }\put(3,3.7){ \times }\put(4,3.7){ \times }\put(3,2.4){ \times }\put(4,2.4){ \times }\put(3,2.7){ \odot }\put(4.05,2.7){ \odot }\put(3,3.4){ \odot }\put(4,3.4){ \odot }\end{picture}$

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