Q3 of 17 Page 157

Fill in the blanks

Oxygen ………….burn, but …………. burning.

Oxygen does not itself burn but supports burning.

Explanation:


i. When the wood in a fire is burning low, we blow it with a blower.


ii. It has been observed that the fire flares up and begins to burn vigorously.


iii. After sometime the burning slows down again.


iv. This means that oxygen does not itself burn, but supports burning.


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Fill in the blanks

Some………….. substances absorb ………….. from the air.

 3

Fill in the blanks

It is mandatory to treat ……………. before letting them out.