Iron + sulfur -
iron(II) sulfide

13. a covalent bond between two atoms is likely to be polar if: a. one of the atoms is much more electronegative than the other. b. the two atoms are equally electronegative. c. the two atoms are of the same element. d. the bond is part of a tetrahedrally shaped molecule. e. one atom is an anion.

Ahypothesis must be testable and falsifiable to be considered scientific a. trueb. false

Light waves travel than sound waves.