HESI A2 CHEMISTRY

HESI A2 CHEMISTRY Chemistry Note Cards for HESI ENTRANCE EXAM QUESTION 1. Matter that has a definite shape and volume Solid QUESTION 2 Matter that changes in volume with changes in temperature and pressure Gas QUESTION 3 A change of matter is when no change is made to the chemical composition of a substance. Physical QUESTION 4 Simplest of substances and is represented by a letter or letters Element QUESTION 5 Law that states that matter can neither be created nor destroyed during a chemical reaction Law of observation of mass QUESTION 6 The breakin of bonds and reforming of new bonds to create new chemical compounds with different chemical formulas with different chemical properties Chemical reaction 5 main chemical reactions Synthesis Decomposition Combustion Single replacement Double replacement QUESTION 8 Chemical reaction in which 2 elements combine to form a product Synthesis QUESTION 9 Chemical reaction that is the breaking of a compound into component parts Decomposition QUESTION 10 The chemical reaction that is the reaction of a compound with oxygen Combustion QUESTION 11 Chemical reaction that consists of an active metal reaction with an ionic compound creating a new compound Single replacement QUESTION 12 Chemical reaction involving 2 ionic compounds; the reactant yields “switched prtners” Double replacement QUESTION 12 How elements are arranged in the periodic table By their chemical properties Number that represents the # of protons that an element has Atomic number QUESTION 14 Average of the masses of each of it’s isotopes as they occur in nature Atomic mass QUESTION 15 Mass number – atomic number = #of neutrons in an element QUESTION 16 Columns of the periodic table = Groups QUESTION 17 Rows of the periodic table = Periods QUESTION 18 Group IA = charge +1 QUESTION 19 Group IIA= charge +2 QUESTION 20 Group IIIA = charge +3 Group VA = charge -3 QUESTION 22 Group VA = charge -2 QUESTION 23 Group VIIA = charge -1 QUESTION 24 Charge of noble gases 0 QUESTION 25 Positively charged ions Protons QUESTION 26 Negatively charged ions Electrons QUESTION 27 Neutral ions Neutrons # of proteins in an element = Atomic number QUESTION 29 proteins + neutrons = mass number QUESTION 30 In reactions, atoms try to reach stable electron configurations. Chemical QUESTION 31 reactions take place in the nucleus, to obtain stable nuclear configurations. Nuclear QUESTION 32 Word used to describe the emission of particles from an unstable nucleus. Radioactivity QUESTION 33 The particles that are emitted during radioactivity Radiation