chapter 7: chemical energy Flashcards
what is thermodynamics
the study of energy and its transformations
what is thermochemistry
relationship between chemical reactions and energy changes involving heat
what is energy
the ability (or capacity) to do work or transfer heat.
what is work
Energy used to cause
an object that has mass
to move
what is heat
Energy used to cause
the temp of an object
to rise
what is force
any kind of push or pull exerted on an object
what is the formula for force
f = m x g
what does g stand for
acceleration due to gravity; 9.8 m/s^2
what is the magnitude of work formula
w = F x d = m x g x d d = distance m = mass F = force g = gravity
what is another name for heat
thermal energy
what direction does heat flow
warmer objects to cooler objects
what are some characteristcs of heat and work
- energy is being exchanged between two objects
- energy can flow into or out of the subject studied
- dont exist before or after the state of change
what types of energy are there
potential and kinetic
what is electrical energy
KE associated w/ flow of electrical charge
what is heat or thermal enrgy
KE associated w/ molecular motion
what is light or radiant energy
KE associated with energy transitions in an atom
what is nuclear energy
PE in the nucleus of atoms
what is chemical energy
PE due to the structure of the atoms
what is kinetic energy
energy that is being transferred (motion)
what is the kinetic energy formula
KE = 1/2mv^2
what does KE depend on
the mass and speed of the object
do atoms and molecules possess KE
yes
what is potential energy
energy that is stored in an object
when does PE arise
no force operating on the on
what does PE depend on
mass, height, the gravitational
what is the formula for PE
m x g x h
what is the unit for energy
Joule (J)
who was the energy SI unit named after
James Joule
what does 1 joule equal
1 kgm^2/ s^2
what is a non-SI unit that is still used
calorie (cal)
how many joules does one calorie equal
4.184 J
what is the value of the nutritional calorie
1000 cal (1kcal)