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CHEM 7 PT
CHEM 6 PT
Term | Definition |
---|---|
thermochemistry | The branch of chemistry that studies the heat transfers that accompany chemical or physical changes |
Factors that affect reaction rate | the temperature of the system, the concentration of the reactants, the inherent properties of the reactants, the presence of a catalyst, and the surface area of the reactants |
Factors that don't affect reaction rate | the reaction's color, the reaction's force, the experiment's location, and the container used |
enthalpy | The total amount of energy in a thermodynamic system |
reaction mechanism | The overall sequence of steps that composes a chemical reaction |
activated complex | A transitional substance that results when a reactant bonds are broken, and persists while product bonds are being formed |
calorimetry | The measurement of enthalpy changes caused by chemical reactions, changes of state, or the formation of a solution |
reaction spontaneity | A reaction's tendency to occur without an outside force or energy being applied to sustain the reaction |
Chemical thermodynamics | the study of the relationship between heat and work within chemical reactions or physical changes of state |
standard molar enthalpy of formation | the amount of heat energy transferred when one mole of a compound is formed from its component elements in their standard states |
first law of thermodynamics | The law that states a thermodynamic system's total amount of energy remains constant, is also called the law of conservation of energy. |
standard state | A substance's state, solid, liquid, or gas, at room temperature (25°C or 298 K) and a pressure of 100 kPa |
Gibbs free energy | The type of free energy that is a thermodynamic function and measures a system's capacity to perform work |
entropy | a measure of the energy unavailable to perform work, is also the measure of randomness, or disorder, of a thermodynamic system |
spontaneous reaction | a chemical reaction in which the reactants are converted into products without the constant addition of energy from outside the thermodynamic system to sustain the reaction |
Rules that apply to Hess's law | CHECK Q2 |
Statements that don't apply to hess's law | "No thermochemical equation can ever be reversed to calculate enthalpy, even if the value is changed" and "If a reaction contains intermediate steps, the overall enthalpy is equal to the last step where the enthalpy changed." |
Activation energy | The minimum amount of energy needed to begin a chemical reaction |
reaction rate | The change in concentration of reactants or products in a chemical reaction per unit of time. |
reaction kinetics | The field of chemistry that deals with reaction mechanisms and reaction rates. |
Standard molar enthalpy of reaction | the amount of heat transferred when the number of moles of reactants specified in a chemical equation is completely converted into products. |
Standard molar enthalpy of combustion | The amount of heat transferred during the complete combustion of one mole of a reactants in its standard state. |
Hess's Law | The overall enthalpy change in a reaction is the same whether it occurs in one step or a series of steps. |
Law of conservation of energy | The total amount of energy in a thermodynamic system remains constant. |