Chapter 10 Flashcards
nonmechanical energy
the energy possessed by microscopic particles
energy
the ability to do work
work
when an object moves in response to a force applied to the object
kinetic energy
energy of motion
potential energy
stored energy
temperature
based on the sensations of hot and cold. it is a measurement of the kinetic energy of the particles in an object
heat
a form of nonmechanical energy
specific heat
the amount of energy required to raise 1 gram of a substance to 1 C
6 forms of nonmechanical energy
chemical, electrical, electromagnetic (light), sound, magnetic, and heat
is temperature a measure of heat
no, heat is a form of nonmechanical energy, but temperature is a measure of the average kinetic energy in an object based on motion
C to K
+ 273°
calorimeter
a reaction chamber surrounded by a known mass of water
law of conversation of energy
energy is neither created nor destroyed during a chemical change. it can be converted from one form to another
work equation
work = force x distance
unit for energy
joule (J)
exothermic
releases energy into surrounding - burning, freezing, condensation - negative delta H, Hr > Hp
endothermic
absorbs heat energy - cold pack, boiling, melting - delta H is positive, Hr
delta H
enthalpy / heat energy
for determining how much heat is required, the specific heat, and final temperature
Q = M x (delta T) x Cp Heat = Mass x Change in temp x Specific heat
Q lost = Q gained
2 substances combined eventually become the same heat/temp
how much heat is released using equation
4 Fe + 3 O2 = 2 Fe2O3
delta H = -1653 KJ
10.0 g Fe x (1 mole Fe / 55.8 g Fe) x (1653 KJ / 4 mole Fe) -
dimensional analysis
mechanical energy
the energy possessed by macroscopic particles
