ULTIMATE AP Biology Exam Review questions with correct answers

Define the following: isotope, valence shell, covalent bond, ionic bond CORRECT ANSWER Isotope- one of several atomic forms of an element, each with the same # of protons, but different number of neutrons Valence shell- the outermost energy shell of an atom, containing valence electrons involved in chemical reactions Covalent bond- bond where the electrons are shared Ionic bonds- a chemical bond resulting from the attractions between oppositely charged ions Hydrogen bonds result in.... pH is... CORRECT ANSWER Hydrogen bonds result in a weak, polar, and covalent bond between a H+ and a negative ion. pH is the measure of hydrogen ion concentration How many covalent bonds can carbon form? CORRECT ANSWER 4 bonds Hydrogen bonds form between.