11.
The main buffer system of the human blood is

12.
The gas present in the stratosphere which filters out some of the sun's ultraviolet light and provides an effective shield against radiation damage to living things is

13.
The most commonly used bleaching agent is

14.
The nucleus of a hydrogen atom consists of

15.
The heat required to raise the temperature of body by 1 K is called

16.
The nuclear particles which are assumed to hold the nucleons together are

17.
The mass of P4O10 that will be obtained from the reaction of 1.33 gram of P4 and 5.07 of oxygen is

18.
The octane number of zero is assigned to

19.
The metal that is used as a catalyst in the hydrogenation of oils is