Percentage of lead in lead pencils is
1). 0
2). 66
3). 40
4). 80
1. 'Atomic theory' of matter was given by
2. How many neutrons does iron have?
3. Galvanised iron is made by coating iron with
4. The gas used for artificial fruit ripening of green fruit is –
5. The Chairman of the Drafting Committee of the Constituent Assembly of India was
6. Who was the first man to go to space?
7. The tip of the matchstick contains
8. Ilmenite is an ore/mineral of _________.
9. The chemical formula of Ammonia is _____ .
10. Question 3.7:Why does the conductivity of a solution decrease with dilution?