Which one of the following is a microelement?
1). Chlorine
2). Hydrogen
3). Nitrogen
4). Oxygen
Radioactive disintegration of uranium ultimately results in formation of
1). radium
2). thorium
3). polonium
4). lead
Which of the following fibres catches fire least ?
1). Nylon
2). Cotton
3). Rayon
4). Terricot
The greenhouse effect is caused by the higher level of which gas in the atmosphere ?
1). Carbon monoxide
2). Carbon dioxide
3). Nitrous oxide
4). Sulphur dioxide
Natural rubber is the polymer of:
1). isoprene
2). Styrene
3). Butadiene
4). Ethylene