A compound '$$\mathrm{X}$$' when treated with phthalic anhydride in presence of concentrated $$\mathrm{H}_{2} \mathrm{SO}_{4}$$ yields '$$\mathrm{Y}$$'. '$$\mathrm{Y}$$' is used as an acid/base indicator. '$$\mathrm{X}$$' and '$$\mathrm{Y}$$' are respectively
Arrange the following gases in increasing order of van der Waals constant 'a'
A. Ar
B. $$\mathrm{CH}_{4}$$
C. $$\mathrm{H}_{2} \mathrm{O}$$
D. $$\mathrm{C}_{6} \mathrm{H}_{6}$$
Choose the correct option from the following.
Which of these reactions is not a part of breakdown of ozone in stratosphere?
The statement/s which are true about antagonists from the following is/are:
A. They bind to the receptor site.
B. Get transferred inside the cell for their action.
C. Inhibit the natural communication of the body.
D. Mimic the natural messenger.
Choose the correct answer from the options given below: