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| 9505307904 | 1st Law of Thermodynamics | energy of universe is constant | 0 | |
| 9505307905 | 2nd Law of Thermodynamics | process spontaneous in one direction can't be spontaneous in reverse direction | 1 | |
| 9505307906 | state function | ∆H, ∆S, ∆G | 2 | |
| 9505307907 | energy released | bonds formed; exothermic | 3 | |
| 9505307908 | energy absorbed | bonds broken; endothermic | 4 | |
| 9505307909 | ∆H | H(products)-H(reactants) | 5 | |
| 9505307910 | heat of formation | ∆H = ∑H(products)-∑H(reactants) | 6 | |
| 9505307911 | heat capacity | heat ÷ ∆T | 7 | |
| 9505307912 | specific heat | q = mc∆T | 8 | |
| 9505307913 | Gibbs free energy | measure of spontaneity of process | 9 | |
| 9505307914 | ∆G negative | spontaneous | 10 | |
| 9505307915 | ∆G positive | not spontaneous | 11 | |
| 9505307916 | ∆G = 0 | reaction at equilibrium | 12 | |
| 9505307917 | ∆G° | ∆H - T∆S | 13 | |
| 9505307918 | ∆G | ∆G° + RT(lnQ) | 14 | |
| 9505307919 | R (in thermo, not gases) | 8.31 J/mol*K | 15 | |
| 9505307920 | exothermic reaction | reactants start higher than products | 16 | |
| 9505307921 | endothermic reaction | reactants start lower than products | 17 | |
| 9505307922 | entropy | measure of disorder of system | 18 | |
| 9505307923 | particles | in solution have higher entropy values than solids | 19 | |
| 9505307924 | 2 moles of substance | have higher entropy value than one mole | 20 | |
| 9505307925 | entropy change ∆S | ∑S°(products) - ∑S°(reactants) | 21 | |
| 9505307926 | standard state conditions | 1. all gases are at 1 atm 2. all liquids are pure 3. all solids are pure 4. all solutions are at 1-M 5. the energy of formation of an element in its normal state is defined as 0 6. temperature used for standard state values is almost invariably room temperature. standard state values can be calculated for other temperatures, however. | 22 | |
| 9505307927 | heat of vaporization | energy given off when substance condenses | 23 | |
| 9505307928 | heat of fusion | energy taken in by substance when melts | 24 | |
| 9505307929 | addition of catalyst | decreases activation energy only | 25 | |
| 9505307930 | spontaneous endothermic reaction | ∆H > 0 ∆S > 0 | 26 | |
| 9505307931 | spontaneous process | one that proceeds on its own without assistance, they are irreversible unless the surroundings are changed and they can be fast or slow | 27 | |
| 9505307932 | Exothermic Reactions | negative ∆H, favors spontaneity but does not guarantee it. | 28 | |
| 9505307933 | Entropy of a system increases when | gases are formed from solids or liquids, liquids or solutions are formed from solids, the number of gas molecules changes during a chemical reaction | 29 | |
| 9505307934 | standard entropy | S° is the absolute entropy of a mole of a substance at 1 atm and 35°C. J/Mol K. for all elements and compounds the standard entropy is always positive. | 30 | |
| 9505307935 | +∆S | becomes more random; disordered | 31 | |
| 9505307936 | -∆S | becomes more ordered | 32 | |
| 9505307937 | standard molar entropies of elements and diatomics | are not 0 unlike standard molar enthalpies | 33 | |
| 9505307938 | standard free energy | ∆G°(rxn) is the free energy change of a reaction when it occurs under standard conditions; when reactants in their standard states are converted to products in their standard states. | 34 | |
| 9505307939 | ∆G°rx | = ∑n∆G(f°products) - ∑n∆G°reactants | 35 | |
| 9505307940 | spontaneous at all temperatures | -∆H (favorable) +∆H (favorable) | 36 | |
| 9505307941 | nonspontaneous at all temperatures | +∆H (unfavorable) -∆S (unfavorable) | 37 | |
| 9505307942 | spontaneous at low T; nonspontaneous at high T | -∆H (favorable) -∆S (unfavorable) | 38 | |
| 9505307943 | spontaneous at high T; non spontaneous at low T | +∆H (unfavorable) +∆S (favorable) | 39 | |
| 9505307944 | -∆G | the forward process is spontaneous (the reverse is nonspontaneous) | 40 | |
| 9505307945 | +∆G | the forward process is nonspontaneous (the reverse is spontaneous) | 41 | |
| 9505307946 | Phase transitions | if the process is melting, the ∆H is the same as the heat of fusion. if the process is freezing, the ∆H is the negative value of the heat of fusion. if the process is boiling, the ∆H is the heat of vaporization. if the process is condensing, the ∆H is the negative value of the heat of vaporization. | 42 | |
| 9505307947 | what does Q stand for | reaction quotient: the mass action expression at non-equilibrium conditions. the spontaneity of a reaction that has not reached equilibrium has to be measured in terms of ∆G which is not synonomous with ∆G° because the substances are not in standard state | 43 | |
| 9505307948 | Finding ∆G when ∆G° and Q are known | ∆G = ∆G° + RTlnQ | 44 | |
| 9505307949 | Enthalpy (heat) of combustion | the heat released or absorbed (enthalpy change) during the formation of a pure substance from its elements, at constant pressure and usually denoted by ΔHf. | 45 | |
| 9505307950 | Hess's law | The overall enthalpy change in a reaction is equal to the sum of the enthalpy changes of the individual steps of the process. | 46 | |
| 9505307951 | Calorimeter insulated device used for measuring the amount of heat absorbed or released through a chemical or physical process | insulated device used for measuring the amount of heat absorbed or released through a chemical or physical process |  | 47 |
| 9505307952 | bomb calorimeter sealed, insulated container used for measuring the energy released during combustion | sealed, insulated container used for measuring the energy released during combustion |  | 48 |
| 9505307953 | heating curve | a diagram that shows the temperature changes and changes of state of a substance as it is heated |  | 49 |
| 9505307954 | potential energy diagram | a diagram that shows the changes in potential energy that takes place during a chemical reaction |  | 50 |
