Which of the following is true about a scientific theory? a. a theory is a proposed explanation for a hypothesis b. a theory can be changed to explain new observations or experimental results c. a theory can be formed after a single experiment d. a theory can never be changed

Select all of the methods through which a drug can enter your body. injection swallowing inhalation absorption

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.

4. propanol and isopropanol are isomers. this means that they have a) the same molecular formula but different chemical properties. b) different molecular formulas but the same chemical properties. c) the same molecular formula and the same chemical properties. d) the same molecular formula but represent different states of the compound