Which of the following substances would you predict to have the highest δhvap?

1.h2
2.f2
3.sif4
4.h2o
5.ar

Option (4) is the correct answer.

Explanation:

Heat of vaporization is defined as the heat energy which is necessarily added to a liquid substance in order to transform the quantity of the substance into a gas.

For example, in there will be presence of strong hydrogen bonding and in order to break this bond high amount of heat energy is required.

Whereas , and are all covalent compounds which are bonded together by Vander waal forces. As these forces are weak in nature hence, they require less amount of heat energy to convert into vapor state.

Hence, they have low value of . Also, Ar is a noble gas and it has only Vander waal forces. So, it will also have low value of .

Therefore, we can conclude that out of the given options have the highest .

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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