Grade 12 Chemistry Exam with Answers, Exams of Advanced Education

Download Grade 12 Chemistry Exam with Answers and more Exams Advanced Education in PDF only on Docsity! Grade 12 Chemistry Exam with Answers Organic compounds - correct answer-: compounds in which carbon atoms are nearly always bonded to each other, to hydrogen atoms, and occasionally nitrogen, oxygen and the halogens. Linear - correct answer-= 180 degrees Trigonal Planar - correct answer-= 120 degrees Tetrahedral - correct answer-= 109.5 degree isomers - correct answer-Molecules that have the same molecular formula, but their atoms are in a different arrangement. Constitutional Isomers - correct answer-: compounds that have the same molecular formula but their atoms are bonded together in a different sequence. Stereoisomers - correct answer-: molecules that have the same molecular formula and sequence of bonded atoms, but differ in the 3-dimensional orientations of their atoms. There are 2 types: 1. Cis-trans isomers - correct answer-: stereoisomers based on a double bond, in which different types of atoms or groups are bonded to each carbon in the double bond. Exist due to lack of free rotation round a double bond, and occur in alkenes when the double bond is NOT located at the end of the chain Enantiomers - correct answer-: stereoisomers which are non-superimposable mirror- image structures. When four non-identical atoms or groups are attached to a tetravalent carbon, the tetrahedral arrangement of the bonds Dipole-Dipole forces - correct answer-an attractive force between polar molecules that cause them to cling together. Hydrogen Bonding - correct answer-: strongest type of DDF, attraction between an H from an NH, FH or OH AND a polar N, O, or F from another molecule London Dispersion forces - correct answer-Weaker attractive force that occurs between all molecules, including non-polar molecules. Increases in strength as molecules get larger. Addition Reactions - correct answer-: atoms are added to a carbon-carbon double or triple bond) Markovnikov's Rule - correct answer-: In an addition reaction, with an asymmetric alkene, 2 products are produced, one is a major product and one is a minor product. The major is the carbon with the most hydrogens attached to it. Elimination reactions - correct answer-: atoms are removed from an organic molecule to form a double or triple bond. Substitution reaction - correct answer-s: a hydrogen atom or functional group is replaced by a different atom or functional group. Note, when with an aromatic compound like benzene, it is called mono-substitution Oxidation reactions - correct answer-: a carbon atom forms more bonds to oxygen atoms or fewer bonds to hydrogen atoms. No reaction with tertiary alcohol Reduction reactions - correct answer-: a carbon atom forms fewer bonds to oxygen atoms or more bonds to hydrogen atoms. (Reverse of oxidation) Esterification/condensation - correct answer-: 2 molecules combine to form a larger molecule, producing water as a second product Neutralization reactions - correct answer-: a rxn between an acid and a base that yields a salt and water Hydrolysis reaction - correct answer-: a molecule is broken apart by adding the hydroxyl group from a water molecule to one side of a bond and the hydrogen atom of a water molecule to other side of the bond. Principle QN - correct answer-Energy level & relative orbital size Orbital shape QN - correct answer--L Magnetic QN - correct answer-Ml Electron Spin QN - correct answer-Ms trigonal planar - correct answer- tetrahedral - correct answer- Trigonal pyramidal - correct answer- Trigonal bipyramidal - correct answer- -Decrease in temperature, Eqm position shifts to the side that does contain the heat term Addition of an inert gas - correct answer-: if they addition of an inert gas does not change the volume, all reactant and product concentrations stay the same (Note: the addition of an inert gas at constant pressure is the same as an increase in volume Solute - correct answer-: a substance that is dissolved in a solution Solvent - correct answer-: a substance that has other substances dissolved in it Solubility - correct answer-: the amount of solute that will dissolve in a given volume of solvent at a given temperature. Molar solubility - correct answer-: the amount in moles of solute (solid ionic compound) in 1L of saturated solution (x value Oxidation - correct answer-: the loss of electrons (LEO) Reduction - correct answer-: the gain of electrons (GER) Oxidizing agent - correct answer-the reactant that causes the other reactant to get oxidized. Reducing agent - correct answer-: the reactant the causes the other reactant to get reduced. Disproportionation - correct answer-when a single element undergoes both oxidation and reduction in the same reaction. Example) Cu+ + Cu+ Cu2+ + Cu(s) Salt bridge - correct answer-completes the circuit between 2 separate half cells. The salt ions migrate to preserve electrical neutrality Dry cell - correct answer-a galvanic cell in which electrolyte has been thickened into a paste Battery - correct answer-: a defined set of galvanic cells connected in series Primary battery - correct answer-: disposable battery that cannot be recharged Secondary battery - correct answer-a rechargeable battery Alkaline batteries - correct answer-: A dry cell that has an alkaline electrolyte in the paste. Button battery - correct answer-: a very small dry cell, usually having an alkaline electrolyte Atomic size - correct answer-: the atomic radius of an element decreases going to the right (across a period) and decreases going up a family. Metallic character - correct answer-: the extent to which an element exhibits the physical and chemical properties of a metal, metallic decreases across a period and decreases up a family. Ionization energy - correct answer-: the energy needed to remove an electron. Increases across a period and increases up a family Electron affinity - correct answer-: the energy that accompanies the addition of an electron to a neutral gaseous atom. Increases across a period and increases up a family Electronegativity - correct answer-: the tendency for an atom to attract electrons to itself when it is chemically combined with another element. Increases across a period, and increases up a family Family trends - correct answer-: as you move up, Zeff is constant, but valence e- are in lower energy levels. Therefore the electrons are closer to the nucleus. Period trends - correct answer-as you move left tp right, the # of shielding core electrons remains constant but the # of protons increases, Therefore Zeff increases, the protons pull on valence e- more strongly, thus pulling them closer to the nucleus Effective nuclear charge Zeff - correct answer-: the charge that the overall outshell electrons experience after the core electrons shield the nuclear charge through core e- repulsions. Zeff = charge of nucleus = # lof non-valence (core) electrons. Equivalence point - correct answer-: the point in titration when just enough acid and bases have mixed for a complete reaction (no acid/base left) Buffered solution - correct answer-: one that resists change in PH when a moderate amount of acid or base is added to it. Bronsted-Lowry theory of acids - correct answer-: an acid is a proton donor Bronsted-Lowry theory of bases - correct answer-: a base is a proton acceptor Amphiprotic - correct answer-: a molecule or ion that can accept or donate a proton thus acting as an acid or base.