Acertain atom of oxygen contains 8 protons, 8 neutrons, and 8 electrons. another atom of unknown identity contains 9 protons. which of the following must be true about this unidentified atom?
a. it is an isotope of oxygen
b. its atomic mass is a decimal number
c. it has 9 neutrons in its nucleus
d. it cannot be an atom of oxygen

Molecular models of two different substances are shown below. in the molecule on the left, the oxygen atom pulls on electrons more strongly than the hydrogen atoms. in the molecule on the right, the two oxygen atoms pull on the shared electrons with the same strength. water molecule, h,o oxygen molecule, oz when the two substances are put in the same container, they do not attract each other. why does this happen? a. they both contain oxygen. b. one is polar and one is nonpolar. c . they are both polar. d. they contain different elements.

Most animal cells membranes have proteins that pump ions out of the cell and potassium ions into the cell

How can an organ, such as the lungs, work for multiple body systems?