Carbon dioxide is produced by all of the following except
1). Burning fossil fuels
2). Global warming
3). Cement production
4). Deforestation
1. Which of the following elements has the lowest melting point?
2. Question 2.2:Give an example of solid solution in which the solute is a gas.
3. Plaster of Paris is made by partial dehydration of
7. The mass of one Avogadro number of helium atom is