Question : Heavy water is used as a coolant in nuclear reactors. Heavy water is

Option 1: Water rich in minerals

Option 2: Ozonised water

Option 3: Water containing minerals of heavy metal

Option 4: Water containing heavy isotope of hydrogen

Question : In an experiment, it was observed that metal A is 19 times heavier than water and metal B is 9 times heavier than water. In what ratio are metals A and B mixed so that the mixture thus obtained is 15 times heavier than water?

Option 1: 2 : 3

Option 2: 1 : 3

Option 3: 3 : 1

Option 4: 3 : 2

Question : Which type of pathogen causes the water-borne disease Typhoid fever?

Option 1: Algal

Option 2: Parasitic

Option 3: Protozoan

Option 4: Bacteria

Question : Which of the following metal salts is responsible for permanent hardness in water?

Option 1: KCl

Option 2: Nacl

Option 3: Ca(HCO₃)₂

Option 4: CaCl₂

Question : A diagonal relationship is found between which pair of the following elements?

Option 1: Li and Mg

Option 2: Be and B

Option 3: Be and Mg

Option 4: Na and Mg