Which of the following elements belongs to the halogen group?
The process of conversion of a solid directly into a gas without passing through the liquid state is called:
Which of the following compounds is used in the manufacture of fertilizers and explosives?
The oxidation state of oxygen in most of its compounds is:
The process of converting vegetable oils into solid fats by the addition of hydrogen is known as:
The metal used to extract copper from its ore by smelting is:
The phenomenon of an atom or molecule absorbing light and then re-emitting it in all directions is called:
Which of the following is an example of an exothermic reaction?
Which of the following is the main component of natural gas?
The pH of a solution with a hydrogen ion concentration of 1 x 10^-6 M would be: