Answer:
Follows are the solution to this question:
Explanation:
Please find the image file of the chemical reaction in the attachment:
In a water medium, the CH3- type CH 3Li is a heavy nucleophile that attacks the carbonyl carbon atom to form the alkoxide ion, which will then be protonated to form alcohol. 
 
        
             
        
        
        
"The other halogens are not as electronegative and so other hydrogen halides cannot form hydrogen bonds between molecules. Only London Forces are formed. - Therefore more energy is required to break the intermolecular forces in HF than the other hydrogen halides and so it has a higher boiling point."
not a hack link, just stating where i got your answer from! - 
https://www.mytutor.co.uk/answers/17558/A-Level/Chemistry/Explain-the-unusually-high-boiling-point-of-HF/
 
        
             
        
        
        
Answer: Option (a) is the correct answer.
Explanation:
Ionic salts are defined as the salts which tend to contain ionic bonds as there occurs transfer of electrons between its combining atoms. 
So, when an ionic salt melts or it is dissolved in water then it will dissociate into its respective ions and as electricity is the flow of electrons or ions. Hence, this salt is then able to conduct electricity.
As covalent compounds are insoluble in water so, they do no dissociate into ions. Hence, they do not conduct electricity.
Similarly, metallic and network solids do not dissociate into ions either when melted or dissolved in water. Therefore, they also do not conduct electricity.
Thus, we can conclude that when a white crystalline salt conducts electricity when it is melted and when it dissolves in water then this bond is of ionic type.