CHEM LAB 2 Flashcards
LABORATORY
A reaction in which heat is absorbed and the temperature of the surroundings falls
Endothermic
A reaction in which heat is evolved and the temperature of the surroundings rises.
Exothermic
One that proceeds on its own without any continuous external influence
spontaneous reaction
The sum of kinetic and potential energies for each particle in a system
internal energy (U)
The enthalpy change for a reaction.
Heat reaction
A system that freely exchanges energy and matter with its surroundings.
open system
A system that exchanges only energy with its surroundings, not matter.
closed system
A system that does not exchange energy or matter
isolated system
The energy transferred from one object to another as the result of a temperature difference between them.
Heat, q
Energy cannot be created or destroyed, it can only be converted from one form into another.
(AUsys + AUsurrounding = 0). the total internal energy of an isolated system is constant (AUss =
q + w)
first law of thermodynamics
The amount of heat necessary to raise the temperature of 1 gram of substance by 1°C.
specific heat (s)
The amount of heat necessary to raise the temperature of a given quantity of the substance by 1°C.
Heat capacity (c)
The amount of heat necessary to raise the temperature of 1 mol of substance by 1°C.
molar heat capacity
The heat change in a reaction or process at constant pressure.
enthalpy change (delta h)
A function or property whose value depends only on the present condition of the system, not on the path used to arrive at that condition.
(Examples in thermodynamics are H, U, G and S)
state function
