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CHEM 112 FINAL EXAM 202 5 /ACTUAL 200 EXAM
QUESTIONS WITH CORRECT VERIFIED ANSWERS/LATEST
UPDATE-2025 /ALREADY GRADED A+
quickly ANSWER gases react more [slowly/quickly] than liquids concentration, temperature, catalyst, diffusion rate ANSWER factors affecting reaction rates reaction rate ANSWER the speed of a chemical reaction in molarity/second change in concentration of B/change in time ANSWER average rate of appearance of B instantaneous rate ANSWER the rate of reaction at a particular moment initial rate ANSWER rate at time = 0 rate law ANSWER an equation that shows how the rate depends on the concentrations of reactants K[A]^m x [B]^n ANSWER general form of a rate law rate constant ANSWER the units of this can be found by dividing M/s by the units of concentration zero ANSWER if a reaction is unchanged by concentration, it is this order
first ANSWER if the rate change is proportional to concentration change, the reaction is this order second or greater ANSWER if rate change is exponential, the reaction is this order does ANSWER the rate of a reaction [does/does not] depend on concentration does not ANSWER the rate constant [does/does not] depend on concentration first-order reaction ANSWER a reaction whose rate depends on the concentration of a single reactant raised to the first power ln[A] sub t = ANSWERKt + ln[A] initial ANSWER the integrated rate law straight, - K, ln[A] initial ANSWER first-order reaction graphs of ln[A] sub t versus time gives a [straight/curved] line with this slope and this y-intercept second order reaction ANSWER a reaction whose rate depends on the reactant concentration raised to the second power or on the concentrations of two different reactions, each raised to the first power straight, K, t/[A] initial ANSWER second-order reaction graphs of 1/[A] sub t gives a [straight/curved] line with this slope and this y-intercept first ANSWER the graph of the natural log of this-order reaction versus time is linear second ANSWER the graph of 1/[A] of this-order reaction versus time is linear
reaction mechanism ANSWER the process by which a reaction occurs elementary reaction ANSWER a reaction that occurs in a single step molecularity ANSWER the number of molecules that participate in a reaction unimolecular ANSWER describes a reaction in which only one molecule is involved multistep mechanism ANSWER a reaction that consists of a sequence of elementary reactions intermediate ANSWER a substance in a reaction that is neither reactant nor product homogeneous catalyst ANSWER a catalyst that is present in the same phase as the reacting molecules
heterogeneous catalyst ANSWER a catalyst that exists in a different phase from the reactant molecules a catalyst is present at the beginning of a reaction and an intermediate is formed during it ANSWER the difference between catalysts and intermediates Arrhenius ANSWER this acid yields H+ ions in water Arrhenius ANSWER this base yields OH-ions in water
Bronsted-Lowry ANSWER this acid donates a proton to another substance Bronsted-Lowry ANSWER this base accepts a proton from another substance amphiprotic ANSWER describes a substance that can act as either an acid or a base conjugate acidANSWERbase pair ANSWER an acid and base that differ only in the presence or absence of a proton strong acid ANSWER this substance completely transfers its protons to water, leaving no undissociated molecules in solution weak acid ANSWER this substance only partially dissociates in water and therefore exists as a mixture of protons and undissociated constitutent auto-ionization ANSWER the donation of a proton from one water molecule to another acidANSWERdissociation constant ANSWER the equilibrium constant for an acid stronger ANSWER the larger the value of Ka, the [stronger/weaker] the acid percent ionization ANSWER (concentration of substance ionized / original concentration) x 100%
solubility constant ANSWER this constant is equal to the product of the concentrations of the ions involved in the equilibrium reaction, each raised to the power of its coefficient complex ion ANSWER an assembly of a metal ion and the lewis bases bonded to it formation constant ANSWER the equilibrium constant for a complexation reaction amphoteric ANSWER these oxides and hydroxides can behave as either acids or bases selective precipitation ANSWER separation of ions in an aqueous solution by using a reagent that forms a precipitate with one or a few of the ions spontaneous process ANSWER process that can proceed without external assistance reversible process ANSWER a process that reverses direction whenever a very small change is made to the system irreversible ANSWER spontaneous reactions are [reversible/irreversible] entropy ANSWER this property is associated with the randomness in a system isothermal ANSWER describes a process at constant temperature
microstate ANSWER the single possible arrangement of the positions and kinetic energies of gas molecules when a gas is in a specific thermodynamic state increases ANSWER entropy [increases/decreases] with volume, temperature and number of molecules increases ANSWER entropy [increases/decreases] for processes in which the number of gas molecules increases more ANSWER a molecule containing hydrogen will transfer a proton only if the X in the HX bond is [more/less] electronegative more ANSWER in an ionic hydride (where H acts as an anion, such as NaH), H will only transfer a proton if it is [more/less] electronegative than the cation neither ANSWER non-polar bonds produce [acidic/basic/neither] aqueous solutions stronger ANSWER the greater the stability of the conjugate base, the [stronger/weaker] the acid bond strength ANSWER in binary acids, this is the most important factor in determining acid strength less ANSWER bond strengths change [more/less] moving across a row in the periodic table than they do down a group oxyacid ANSWER acids in which OH groups and possibly additional O2 atoms are bound to a central atom
decreases ANSWER in any spontaneous process at constant temperature and pressure, the free energy always [increases/decreases] <, spontaneous ANSWER when Q is [ < / > / =] K, there is an excess of reactants relative to the products and the forward reaction is [spontaneous/non- spontaneous]
ANSWER when Q is [ < / > / =] K, the reverse reaction is spontaneous = ANSWER when Q is [ < / > / =] K, the process is at equilibrium negative ANSWER at constant T and P, if the forward reaction is spontaneous, delta G is [positive/negative] zero ANSWER at constant T and P, if the reaction is at equilibrium, delta G is equal to this positive ANSWER at constant T and P, if the forward reaction is non- spontaneous (but the reverse reaction is spontaneous), delta G is [positive/negative] endothermic ANSWER reactions with positive delta H are this non-spontaneous ANSWER reactions with negative delta G are this delta G ^o ANSWER standard free energy change
delta G ANSWER standard free energy change under non-standard conditions pure solid ANSWER the standard free energy condition of a solid pure liquid ANSWER the standard free energy condition of a liquid 1 atm ANSWER the standard free energy condition of a gas one molar concentration ANSWER the standard free energy condition of a solution H2O and H+ ANSWER if a reaction is in acidic solution, oxygen and hydrogen are balanced by adding these, respectively OHA- AND H2O ANSWER if a reaction is in basic solution, oxygen and hydrogen are balanced by adding these, respectively voltaic cell ANSWER a device in which the transfer of electrons takes place through an external pathway rather than directly between reactants anode, cathode ANSWER by physically separating the halves of a redox reaction, we create a flow of electrons from an external circuit from [cathode/anode] to [cathode/anode] volt ANSWER the potential difference required to impart one joule of energy to a charge of one coulomb electromagnetic force ANSWER force that pushes electrons through the external circuit
mineral ANSWER solid, inorganic compound that is usually an elemental metal pyrometallurgy ANSWER the use of heat to alter or reduce a mineral (important for the reduction of iron) calcination ANSWER the heating of an ore to bring about its decomposition and the elimination of a volatile product roasting ANSWER thermal treatment that causes reactions between ore and furnace atmosphere (includes oxidation smelting ANSWER materials formed separate into layers slag ANSWER formed when a basic metal oxide reacts at high temperatures with molten silica battery ANSWER a portable, self-contained electrochemical power source that consists of one or more voltaic cells fuel cell ANSWER voltaic cells that can convert the thermal energy released by the combustion of fuels to electrical energy (not batteries because they are not contained-require input of fuel) corrosion reactions ANSWER spontaneous redox reactions in which a metal is attacked by some substance in its environment and converted into an unwanted compound electrolysis reactions ANSWER processes driven by an outside source of electrical energy
metal complex ANSWER an assembly of a central metal ion bonded to a group of surrounding molecules or ions coordination compounds ANSWER compounds containing complexes ligands ANSWER the molecules bound to the metal ion in a complex. Most are either polar molecules or anions coordination number ANSWER the number of atoms directly bonded to the metal ion coordination sphere ANSWER the central metal and the ligands bonded to it donor atom ANSWER the atom of the ligand directly bound to the metal monodentate ligands ANSWER ligands with one donor atom that can occupy one site in a coordination sphere polydentate ligands ANSWER have two or more donor atoms (also known as chelating atoms porphine ANSWER molecule that can bind to a metal using the four nitrogen atoms as donors absorption spectrum ANSWER the amount of light absorbed by a sample as a function of x lanthanide contraction ANSWER the filling of 4F orbitals through lanthanide
nucleus positron emission ANSWER release of a particle with the same mass as an electron but opposite charge nuclear transmutation ANSWER a nuclear reaction induced by collision between a nucleus and a neutron faster ANSWER the higher the nuclear charge, the [faster/slower] the particles must be moving to bring about reaction mass defect ANSWER the difference between the mass of a nucleus and the sum of its constituent nucleons mass defect ANSWER this happens because energy is released when nucleons come together, and energy is accompanied by mass nuclear binding energy ANSWER the energy needed to separate a nucleus into its individual nucleons bonding molecular orbital ANSWER the lower-energy molecular orbital that concentrates electron density between the two nuclei antibonding molecular orbital ANSWER the high-energy molecular orbital with low electron density between the nuclei sigma molecular orbitals ANSWER molecular orbitals in which the electron density is centered about the internuclear axis
molecular orbital diagram ANSWER shows the two interacting atomic orbitals on the left and right and the newly formed molecular orbitals in the middle bond order ANSWER half of the difference between the number of bonding electrons and the number of antibonding electrons equal to ANSWER the number of molecular orbitals formed is [greater than/less than/ equal to] the number of atomic orbitals combined equal ANSWER atomic orbitals combine most effectively with other atomic orbitals of [greater/lower/equal] energy lowered, raised ANSWER as overlap between atomic orbitals increases, the energy of the bonding molecular orbital is [raised/lowered] and the energy of the antibonding molecular orbital is [raised/lowered] pi molecular orbitals ANSWER formed by two overlapping 2p orbitals with electron density concentrated above and below the connecting line between the nuclei crystalline solid ANSWER a solid in which the atoms, ions or molecules are ordered in well-defined three- dimensional arrangements. Usually have faces amorphous solid ANSWER solid in which particles have no orderly structure unit cell ANSWER the repeating unit of a solid crystal lattice ANSWER a three-dimensional representation of a crystalline solid
easier ANSWER it is [easier/more difficult] for the first element in any group to form pi bonds than members lower in the group silicates ANSWER compounds in which a silicon atom is surrounded in a tetrahedral fashion by four oxygens band structure ANSWER the electronic structure of a bulk solid (different for conductors, semi-conductors and insulators) band gap ANSWER the energy gap in insulators and semi-conductors that separates a filled band from an empty one elemental ANSWER these semiconductors contain only one type of element valence band ANSWER the band that forms from the antibonding orbitals decreases ANSWER moving down a group the band gap between atoms [increases/decreases] increases ANSWER band gap [increases/decreases] with increasing distance in period columns between the two participating atoms doping ANSWER the process of adding small amounts of impurity atoms to a semiconductor n-type semiconductor ANSWER a semiconductor that has been mixed with atoms with extra valence electrons that readily jump to the unoccupied antibonding molecular orbitals, increasing conductivity
p-type semiconductor ANSWER a semiconductor that has been mixed with atoms with fewer valence electrons, leaving holes for other valence electrons to enter, increasing conductivity photoconductivity ANSWER the ability of a semiconductor to become more conductive by having one or more of its electrons promoted by light of appropriate wavelength solar cell ANSWER a semiconductor device that converts photons from the sun into electricity
