The ratio of pure gold in 18 carat gold is
1). 100%
2). 80%
3). 75%
4). 60%
2. Water can be separated from alcohol water mixture by
3. Which of the following is ozone depleting pesticide ?
4. The value of gas constant R in Ergs deg–1 mole–1 is
5. This group of alumino silicate minerals is widely used In making electrical insulators
6. Which of the following vitamins contain nitrogen?