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Carbon and its Compounds — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceCarbon and its Compounds4 Marks
Question
Read the following and answer any three questions from (i) to (iv).

As neutral atom carbon has electronic configuration $\text{K}\ \ \ \text{L}\\2\ \ \ \ 4$ To gain inert gas configuration carbon can either donate 4 valence electrons (helium gas configuration) or gain 4 electrons (neon gas configuration), but it cannot do so. To acquire inert gas configuration carbon can only share its 4 valence electrons with other atoms forming covalent bonds. A covalent bond can be defined as a chemical bond formed between two atoms by mutual sharing of valence electrons so that each atom acquires the stable electronic configuration of the nearest noble gas. The concept of covalent bonds was given by Langmuir and Lewis to explain bonding in non-ionic compounds. The covalent bonds are of three types. If each atom contributes one electron, the covalent bond formed is called a single covalent bond and is represented by a single line (-) and if each atom contributes two electrons, the covalent bond formed is called a double bond and is represented by a double line (=) and if each atom contributes three electrons, the covalent bond formed is called a triple bond and is represented by a triple line $(\equiv).$

  1. Which compounds do not contain a double bond?

  2. Write compounds which contains a triple bond?

  3. Which molecules has all its atoms joined together by double covalent bond? Give two example.
                                             
                                         OR
  4. A) Langmuir and Lewis has given which concept?

    B) Explain three types of covalent bonds?  
✓

Answer

  1. (b) II and III only

Explanation:

Both NH3 and HCI have single bonds.

  1. (a) N2

Explanation:

$\text{N}\equiv\text{N}$

  1. (a) Single.
  1. (c) Carbon dioxide.
  1. (c)

Explanation:

In chlorine molecule, both chlorine atoms contribute one electron and thus share single electron pair to form single covalent bond. As shared pair is shared by both atoms, they acquire inert gas configuration of argon atom in valence shell.

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