What compound name belongs in box(1) in figure 3? what type of bond belongs in box (3) in figure 3?

            Box 1  = Sodium Chloride

           Box 3  =  Covalent Bond

Explanation:

Naming NaCl:

                     Ionic compounds are named as;

          i) The positive specie is named first.

          ii) The negative specie is named after.

Example: In NaCl, Sodium is the positive cation i.e. Na⁺ hence, it is named first followed by the name of negative anion which is Cl⁻ (chloride). Therefore, the name given to NaCl is Sodium Chloride.

Covalent Bond:

                This type of bond is formed between atoms by mutually sharing their valence electrons. The type of bond depends upon the electronegativity difference between the atoms. If the electronegativeity difference is greater than the bond will be polar covalent bond or if the difference is small than the bond will be non polar colvalent bond.

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.