Question

I am black when you buy me, red when you use me and gray when you throw me away. What am I?
Fire
Charcoal !
Sand
Cement; Winners will be declared by 30th November 2019

Answer 1

Answer:

when we extract charcoal,it is black

when we use it, we burn it ,it is red.

when it is burned , the ash formed is grey

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Answer 2

I am black when you buy me, red when you use me and gray when you throw me away. I am charcoal.

Explanation:

• Charcoal is the only option among the four which is black in its original state. Thus when it is bought it is black.

• Charcoal is a fossil fuel. When burnt it glows with a red colour which acts as the fuel for the fire. Thus it is red when used.  

• Once the charcoal is completely burnt it undergoes a chemical change and changes into ashes and cinder. The ashes are ash as the name suggests or grey in colour. The ashes are of no use and are thrown away. Thus the answer is ‘charcoal’.