An unknown compound’s semicarbazone melts at 162-165 degree Celsius. The compound does not give a silver mirror in the Tollens’ test. On reaction with KI/I2, NaOH/H2O no straw yellow precipitate forms. Identify the unknown. Explain your reasoning.

Benzophenone

Explanation:

Given that:

an unknown compound’s semicarbazone melts at 162° -165°

The compound does not give a silver mirror in the Tollens’ test.

On reaction with KI/I2, NaOH/H2O no straw yellow precipitate forms.

The objective is to identify the unknown compound.

Since the unknown compound result to a semicarbazone, we can deduce that the unknown compound is a carbonyl compound. A carbonyl compound is either an aldehyde or ketone in nature. Also, the absence of  silver mirror in the Tollens’ test carried out in the reaction confirms that the compound is a ketone because  ketones will  never give a silver mirror in Tollens’ test.

Similarly, on reaction with KI/I2, NaOH/H2O no straw yellow precipitate forms,  that is an iodoform test. That implies that a keto-methyl group is absent in the unknown compound.

Finally, since the unknown compound melting point is between 162° -165° and Benzophenone semicarbazone  melting point is 164°.

We can conclude that the unknown  compound is Benzophenone semicarbazone  

the answer is either b or c

both adhesion and cohesion are attractions.

they are different in that adhesion is the force of attraction between the molecules of two different substances, whereas cohesion is the force of attraction between molecules of the same substance.

possible examples include capillary action, in which the adhesion between water and glass causes the water to rise in a narrow tube against the force of gravity.

because of hydrogen bonding, water is extremely cohesive.

this causes molecules on the surface of water to be drawn inward, which is why drops of water form beads on smooth surfaces.

hope this .