Thermochemistry Flashcards
The amount of heat required to change the temp of an object by exactly 1 C
Heat capacity
In any chemical or physical process, energy is neither created nor destroyed
Law of conservation of energy
A unit of heat energy
Calorie
A form of energy that always flows from a warmer object to a cooler object
Heat
A process that loses heat to its surrounding
Exothermic process
A device used to measure the amount of heat absorbed or released during chemical physical processess
Calorimeter
A process that absorbs best from its surroundings
Endothermic process
The capacity to do work or to supply hear
Energy
The amount of heat required to raise the temperature of 1 gram of a substance by 1 C
Specific heat
Energy released
Exothermic
Energy absorbed
Endothermic
Specific heat of water
4.18
When doing a hess’s law question and you flip the equation you must do what to the delta h
Multiply it by -1
one kilocalorie equals how many joules
4,184
How many joules are in one calorie
4.184
What is 1 atm in celucius and Kelvin and kpa
25 celcius
298 Kelvin
101 kpa
In an open system what can enter
Energy and matter can flow into and out of the system
Heat energy can also flow in and out of the system
In a closed system what can be exchanged
NO MATTER OR ENERGY CAN BE EXCHABGED
Heat energy can be transferred in and out
In an isolated system what can be exchanged
NOTHING CAN ENTER AND NOTHING CAN LEAVE
In an isolated system the internal energy stays
Constant
For heat of formation, when balancing the equation do you try to increase the product to match the reactant or use fractions
Ex 2H2 + O2 —-> 2H2O
. Or
H2 + 1/2O2 ——> H2O
Use fractions! Remember we can only use one mole of the substance so don’t be afraid to use fractions
When a bond breaks energy is ________
Absorbedb
When a bond is formed energy is ________
Released
a calorimeter is what type of system
Isolated
Amount of energy required to change phase
Enthalpy
The molar heat of fusion
Heat absorbed by one mole of substance melting
What is the equation and unit for heat capacity
C(subscript) h = q/ delta T
Unit: J/ C (degrees) or any variation with kilojoules and Kelvin and stuff
