Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsShort Answer Type

81.

What are petrochemicals?

118 Views

82.

Why is petroleum called liquid gold?

270 Views

83.

What does L.P.G. stand for?

124 Views

84.

What are gasoline additives?

108 Views

Advertisement
85.

What are the main constituents of LPG?

183 Views

86. What are alkanes and cycloalkanes ?

122 Views

Advertisement

87. Discuss the structures of alkanes.


Alkanes contain only carbon-carbon and carbon - hydrogen single bonds. For example methane.



Therefore, carbon in alkanes is sp3 - hybridised. Since sp3 hybridised carbon has four half filled sp- orbitals, therefore, it forms four σ-bonds. These four bonds are directed towards the corners of a regular tetrahedron. In other words, the angle between any two adjacent bonds is 109° - 28' (tetrahedral angle).

In methane molecule, carbon lies at the centre of the tetrahedron while the four hydrogens are present at the corners of vertices of the regular tetrahedron. This implies that; each face of the tetrahedron is an equilateral triangle and has three bonds.
161 Views

Advertisement
88.

In the alkane H3C - CH2 -C(CH3)2 -CH2 - CH(CH3)2, identify 1°, 2°, 3° carbon atoms and give the H atoms bounded to each one of these.

146 Views

Advertisement
89.

Write structures of different chain isomers of butane  (C4H10).

143 Views

90. In how many ways, you can join five carbon atoms and twelve hydrogen atoms of C5H12 ?
133 Views

Advertisement