Transcript Energy and Matter

Energy and Matter
Energy

Energy- the ability to do work such as
moving matter a distance causing a heat
transfer between two objects at different
temperatures
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heat
light
electrical
chemical
Two types of Energy
Kinetic Energyenergy contained in a
moving object
 Potential Energy- is
stored energy that is
latent but available
for use.
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Energy Measurements
– Calories (cal)= 4.184 J
– BTU
– Joules (J)- the work done when one kg is
accelerated 1 m per second (1J= 1kg X m /
s.
– KWh
Power

The rate of doing work
Heat

The total kinetic energy of molecules and
atoms in a substance associated with
bulk motion of the substance.
Temperature
is the speed of the motion of a typical atom
or molecule in a substance
Thermodynamics and Energy
Transfers
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First Law of Thermodynamics- energy is
neither created nor destroyed; it can only
change forms (coal to electricity plants. The
plant is limited to the amount of energy that
can be obtained from the coal.)
Second law of Thermodynamics- transfers
of energy decrease the amount of total useful
energy- meaning the entropy of the universe is
increasing or the amount of disorder is
increasing
Conservation of Matter
Under ordinary circumstances, matter is
neither created not destroyed, but rather
are recycled over and over again.
Entropy
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The amount of useful energy lost per amount
of matter.
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Plant absorbing solar energy from sun will loss
some amount of energy
Rabbit absorbing chemical energy by eating a plant,
some energy is lost
Energy lost through entropy disperses as heat and
becomes more scattered or disordered. In this way
entropy is a measurement of disorder, as heat
disperses, entropy – or disorder of energyincreases. Every chemical and physical change
carries with it a measurable change in entropy.