How many pyrrole rings are there in porphyrin

How many pyrrole rings are there in porphyrin?

Options

(a) one (b) two (c) three (d) four

Correct Answer:

four

Explanation:

Four pyrrole rings are there in porphyrin. Chlorophyll structure was studied by Wilstatler, […]

For a spontaneous process, entropy always

For a spontaneous process, entropy always

Options

(a) increases (b) decreases (c) keeps changing (d) remains unchanged

Correct Answer:

increases

Explanation:

The force which is responsible for the spontaneity of a process depends upon […]

An open system

An open system

Options

(a) can neither lose nor gain energy (b) can lose or gain energy (c) can gain or lose matter (d) can lose or gain both matter or energy

Correct Answer: […]

Enantiomers

Enantiomers

Options

(a) are not mirror images (b) are non-superimposable mirror images (c) are superimposable mirror images (d) constitute a mixture of compounds which are mirror images

Correct Answer:

are non-superimposable mirror images

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