vet-tech-chem-ch-2-matter-and-energy

the formation od bubbles of gas throughout a liquid

the temperature at which a liquid changes to gas (boils) and gas changes to liquid (condenses)

the amount of heat energy that raises the temperature of exactly 1 g of water exactly 1 deg C

• the transformation of one state of matter to another
• ex. solid to liquid, liquid to solid, liquid to gas

• a change during which the original substance is converted into a new substance that has a different composition and new chemical and physical properties
• ways to determine:
• - color change
• - gas being produced (not just boiling, e.g. Alka-seltzer in water)
• - heat given off or taken in
• -- e.g. calcium chloride in water is physical change as can be gotten back by boiling off water
• -- e.g. hand warmer - NaCl & Fe filings react to give off heat
• - precipitation (solid forming)

the properties that indicate the ability of a substance to change into a new substance

a pure substance consisting of two or more elements, with a definite composition, that can be broken down into simpler substances only by chemical methods

the change of state of a gas to a liquid

a diagram that illustrates temperature changes and changes of state for a substance as heat is removed

• the change of a gas directly into a solid
• the reverse of sublimation

a pure substance containing only one type of matter, which cannot be broken down by chemical methods

the ability to do work

the kilocalories (or kilojoules) obtained per gram of food types: carbohydrate, fat and protein

the formation of a gas (vapor) by the escape of high-energy molecules from the surface of a liquid

the change of state from a liquid to a solid

the temperature at which a liquid changes to a solid (freezes) or a solid changes to a liquid (melts)

a state of matter that does not have a definite shape or volume

• the energy associated with the motion of particles in a substance
• the transfer of kinetic energy from a high temperature substance to a lower temperature
• measured in:
• - calories
• - kilocalories = 1 food Calorie = 1,000 calorie
• - Joules
• - BTU (British Thermal Unit) - amount of energy needed to raise 1 pound of water at 1 deg F = 252 cal

• the energy required to melt exactly 1 g of a substance at its melting point
• for water:
• - 80 cal (334 J) are needed to melt 1 g of ice
• - 80 cal (334 J) are released when 1 g of water freezes

• the energy required to vaporize exactly 1 g of a substance at its boiling point
• for water:
• - 540 cal (2260 J) are needed to vaporize 1 g of liquid
• - 1 g of steam gives off 540 cal (2260 J) when it condenses

a diagram that shows the temperature changes and changes of state of a substance as it is heated

• the SI unit of heat energy
• 4.184 J = 1 cal
• 1 J = 0.239 cal
• volts * amps * time

• the energy of moving particles
• energy due to motion

a state of matter that takes the shape of its container, but has a definite volume

• the material that makes up a substance
• has mass
• occupies space

the change of state from a solid to a liquid

• the temperature at which a solid becomes a liquid (melts).
• the same temperature as the freezing point

the physical combination of 2 or more substances that does not change the identities of the mixed substances

change in which the physical properties of a substance changes but its identity stays the same

the properties that can be observed or measured without affecting the identity of the substance

• a type of energy related to position or composition of a substance
• stored energy due to:
• - position, e.g. rock at top of mountain
• - condition, e.g. wound spring
• - chemical composition, e.g.

a type of matter composed of elements and compounds that has a definite composition

a state of matter that has its own shape and volume

• a quantity of heat that changes the temperature of exactly 1 g of a substance by exactly 1 deg C
• change in kinetic energy

• 3 forms of matter:
• - solid
• - liquid
• - gas

the change of state in which a solid is transformed directly to a gas without forming a liquid first

• a measure of the average kinetic energy of a substance
• measured in:
• - Celsius - relative temperature scale
• - Fahrenheit - relative temperature scale
• - Kelvin - absolute temperature scale