HESI A2 CHEMISTRY / A2 HESI CHEMISTRY ACTUAL EXAM QUESTIONS WITH CORRECT VERIFIED ANSWERS | 100% PASS (A+ CERTIFIED)

HESI A2 CHEMISTRY / A2 HESI CHEMISTRY ACTUAL EXAM QUESTIONS WITH CORRECT VERIFIED ANSWERS | 100% PASS (A+ CERTIFIED) Metric system Correct Answer Gram (g)- Weight Liter (L)- Volume Meters (m)- distance Metric prefixes Correct Answer Fahrenheit Correct Answer Is a temperature measuring system used only in the U.S., its territories, Belize, and Jamaica Barley used for any scientific measurement except for body temperature Characteristics: -zero degrees is the freezing point of sea water or heave brine at sea level 32 degrees F is the freezing point of pure water at sea level 212 degrees F is the boiling point of pure water at sea level Celsius Correct Answer Sometimes called centigrade is a temperature system used in the rest of the world and by scientific community. Characteristics: Zero degrees is the freezing point of pure water at sea level 100 degrees C is the boiling point of pure water at sea level Most people have a body temperature of 37 degrees C Kelvins Correct Answer (temperature) Is used only in the scientific community Does NOT use Negative Numbers Characteristics: 0 Kelvin is -273 degree C and is thought to be the lowest temperature achievable or absolute zero The freezing point of water is 273 K The boiling point of water is 373K Most people have a body temperature of 310 K but this is never used Important temperatures Correct Answer Melting ice: 21 C and 32 F Normal body temp: 37 C and 98.6 F Boiling water: 100 C and 212 F Atom Correct Answer Nucleus and electron clouds (orbits) Nucleus Correct Answer Consists of protons and neutrons at the the center of the atom. Orbits (electron cloud) Correct Answer _________ of the electron are the outermost parts. Which spin around the nucleus at fantastic speeds. Ground state atoms Correct Answer Tend to have equal numbers of protons and electrons, making them electrically neutral Ionic state (ion) Correct Answer When an atom is electrically charged. Usually occurs when it is in a solution or in the form of a chemical compound. Will have lost electrons, result in a net positive charge or will have gained electrons, resealing in a net negative charge. Cation Correct Answer Positive charge atom Anion Correct Answer Negative charge atom Periodic table Correct Answer Is made up of a series of rows called periods and columns called groups. A table of known elements arranged according to their properties Atomic number Correct Answer # of protons in the nucleus and it defines an atom of a particular element Atomic mass Correct Answer Is the average mass of each of the elements isotopes. # at the bottom of each square in the periodic table; and its usually a decimal #. `Isotopes Correct Answer Different kinds of the same atom that vary in weight # of protons remain the same Compounds Correct Answer Combination with other elements Combine in whole # ratios Chemical equations Correct Answer Reactants -- Products ex. AgNO3 + KCl -- AgCl + KNO3 * Law of Conversation: Mass CANNOT be Created NOR Destroyed Equilibrium Correct Answer A state in which reactants are forming products at the same rate that products are forming reactants. *reversible A + B -- C + D Four ways to increase the reaction rate Correct Answer Increase the temperature Increase the surface area Add a catalyst Increase the concentration of reactants Solutions Correct Answer Defined as a homogenous mixtures of two or more substances Solute Correct Answer Part or parts of being dissolved Solvent Correct Answer Part that is doing the dissolving Can be a liquid in a liquid, a solid in a liquid, or a solid in a solid Types of solutions Correct Answer Compounds Alloys Amalgams Emulsions Compound solution Correct Answer Mixture of different elements to create a single matter Alloys Correct Answer Solid solutions of metal to make a new one such as bronze, which is copper and Tin Amalgams Correct Answer A specific type of alloy in which another metal is dissolved in mercury Emulsions Correct Answer Mixtures of matter that readily separate such as water and oil Percent Concentration Correct Answer Is the expression of concentrations as parts per 100 parts Most are expressed as milligrams (mg) per 100 milliliters (L) Molar concentrations Correct Answer Concentrations of solutions Mol/ L