Read the description given below:-
1. They are nucleic acids
2. They are not associated with proteins
3. They do not exist outside the cell
The description applies to:-

Choose from the list of substances, as to what matches the description given below: [Acetylene gas, aqua fortis, coke, brass, barium chloride, bronze, platinum]. A catalyst used in the manufacture of nitric acid by Ostwald's process.

Companion cells are closely associated with 1 Vessel elements 2 Trichomes 3 Guard cells 4 Sieve elements

Match each substance A to E listed below with the appropriate description given below : A ] Sulphur B] Silver chloride C Hydrogen chloride D Copper [II] Sulphate E] Graphite . A non - metal which reacts with concentrated nitric acid to form its own acid as one of the product