1.A particular ion has a positive two charge. What does this indicate about the particle and its electrons? 2.What type of elements (metals, nonmetals, or metalloids) are involved in ionic bonding? How does an ionic bond occur?
3.What kind of bond would form between iron and copper? How do you know?
4.How do you know if a covalent bond has formed?
5.A bond forms between hydrogen and bromine. Will it be ionic, polar covalent, or nonpolar covalent? How do you determine this?

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

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.