Explanation:
21. The given molecule for cracking is tetradecane.
On cracking it forms one mole of decane (C10H22) and two moles of ethene gas.
The chemical equation is shown below:

22. The essential condition for the formation of an ester is the reaction of alcohol and acid in presence of concentrated sulfuric acid.
Thus among the given options, the first option is the correct one.
23. Isomers of butanol are shown below:
It is 2-butanol.
The position of -OH group changes to the second carbon.
You may find the Lewis dot structure of the CH₃-Br in the attached picture.
Explanation:
In the Lewis dot structure we represent the unpaired electrons using dots.
Bromide have one electron shared with one electron from the carbon to form a covalent bond, while the remaining electrons remains unpaired. We represent the six unpaired electrons of the bromide with dots.
Learn more about:
structure of organic compounds
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Answer:
are in constant motion
Explanation:
according to the kinetic molecular theory, particles of matter
are in constant motion
Asteroids come from the asteroid belt