Hydrocarbons are a class of organic compounds consisting entirely of hydrogen and carbon. Hydrocarbons are generally colourless and hydrophobic with only weak odours. Hydrocarbons are the principal constituents of petroleum and natural gas. They are used as fuels and lubricants as well as raw materials for the production of plastics, fibres, rubbers, solvents, explosives and industrial chemicals. Methane, ethane, propane, butane, etc., are examples of some common hydrocarbons.

Sciwise - A coursebook of Science>Chapter 7 - Combustion and Flame>EXERCISE>Q 1

MEDIUM

8th CBSE

IMPORTANT

Earn 100

Vijay's mother was cooking food on the gas stove. When she suddenly observed a change in the colour of the flame, she told Vijay that the LPG gas in the cylinder was about to finish. Why did she say so? What do you think she observed?

Important Questions on Combustion and Flame

MEDIUM

8th CBSE

IMPORTANT

Sciwise - A coursebook of Science>Chapter 7 - Combustion and Flame>EXERCISE>Q 2

Why can we not use the same type of fire extinguisher for all types of fires?

HARD

8th CBSE

IMPORTANT

Sciwise - A coursebook of Science>Chapter 7 - Combustion and Flame>EXERCISE>Q 1

Of late there has been news of forest fires across the globe. In

2019

, forest fires damaged the Amazon, Australia, and some parts of California. Some scientists believe that these fires are periodical and happen every summer season, while some contend that they are human-made. Find out and discuss in class why do you think these fires occur and how we can prevent such occurrences in future?

EASY

8th CBSE

IMPORTANT

Sciwise - A coursebook of Science>Chapter 7 - Combustion and Flame>EXERCISE>Q 2

Combustion also happens in our body. Do you agree? Why?