Answer: D. They turn red litmus paper blue and taste bitter.
Explanation:
Acids are those substances which either donates hydrogen ions when dissolved in water. They have pH ranging from 1 to 6.9. They are sour in taste. They dissolve metals to give hydrogen gas. They turn blue litmus red.
Bases are those substances which either donates hydroxide ions when dissolved in water or donates a pair of electrons. They have pH ranging from 7.1 to 14. They are bitter in taste. They are slippery in nature. They turn red litmus blue.
Compound A will be 2-chloro-butane which in the presence of sodium methoxide will undergo the elimination of the halogen with a hydrogen from the neighboring atom carbon (not the one with which the halogen in bound), which have less hydrogen atoms, forming the trans-2-butene.
Explanation: by the fact that some or all of the atoms in their molecules are joined in rings containing at least one atom of an element other than carbon