A) because spontaneous means in an instant
Answer:
If carbonyl oxygen of 4-hydroxypentanal is enriched with
, then the oxygen label appears in the water .
Explanation:
- In the first step, -OH group at C-4 gives intramolecular nucleophilic addition reaction at carbonyl center to produce a cyclic hemiacetal.
- Then, one equivalent of methanol gives nucleophilic substitiution reaction by substituting -OH group in cyclic hemiacetal to produce cyclic acetal.
- If carbonyl oxygen of 4-hydroxypentanal is enriched with
, then the oxygen label appears in the water produced at the end of reaction. - Full reaction mechanism has been shown below.
The empirical formula for 200 grams of an organic sample which contains carbon,hydrogen, and oxygen is C3H6O
The following are the statements, which indicates that the fossil record suggests about evolution on Earth:
1. Humans have only recently existed on Earth.
2. The organisms originally lived only in Earth's water.
3. The plants did not have flowers when dinosaurs existed.
The fossil remains have been discovered in the rocks of all the ages. The simplest organisms fossils are witnessed in the oldest rocks, and the fossils of more composite species are found in the newest rocks. This supports the theory of evolution suggested by Darwin, according to which the simple life forms slowly gets evolved into more composite ones.