Vulcanization of rubber is carried out by adding
1). Sulphur
2). Carbon
3). Ozone
4). Phosphorus
1. Atomic number of which of the following elements is greater than that of Copper?
2. Which of the following metals occurs In free state ?
4. The orientation of an atomic orbital is governed by
7. The presence of ozone in the stratosphere is responsible for
8. Question 14.20:Why are vitamin A and vitamin C essential to us? Give their important sources.
9. The isomerism which exists between CH3CHCI2 and CH2CI. CH2CI is