The ideal gas law is important because you can predict how most gases with behave with a simple equation. Here’s how to do it:

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We’re nearly done! Take a peek at the list of concepts below and make sure you’ve got a good handle on them…

Scientific Concepts:

• The terms hot, cold, warm etc. describe what physicists call thermal energy.
• Thermal energy is how much the molecules are moving inside an object.
• The faster molecules move, the more thermal energy that object has.
• There are different scales for measuring temperature: Fahrenheit, Celsius, Rankine and Kelvin.
• Temperature is basically a speedometer for molecules. The faster they are wiggling and jiggling, the higher the temperature and the higher the thermal energy that object has.
• Solids have strong, stiff bonds between molecules that hold the molecules in place. Liquids have loose, stringy bonds between molecules that hold molecules together but allow them some flexibility. Gasses have no bonds between the molecules. Plasma is similar to gas but the molecules are very highly energized. Materials change from one state to another depending on the temperature and these bonds.
• Changing from a solid to a liquid is called melting. Changing from a liquid to a gas is called boiling, evaporating, or vaporizing. Changing from a gas to a liquid is called condensation. Changing from a liquid to a solid is called freezing.
• All materials have given points at which they change from state to state.
• Melting point is the temperature at which a material changes from solid to liquid. Boiling point is the temperature at which a material changes from liquid to gas. Condensation point is the temperature at which a material changes from gas to liquid. Freezing point is the temperature at which a material changes from liquid to gas.
• Heat is the movement of thermal energy from one object to another. Heat can only flow from an object of a higher temperature to an object of a lower temperature.
• Heat can be transferred from one object to another through conduction, convection and radiation.
• Conduction is the wiggle and bump method of heat transfer. Faster moving molecules bump into slower moving molecules speeding them up. Those molecules then bump into other molecules speeding them up and so on increasing the temperature of the object.
• Convection is heat being transferred by currents of moving gas or liquid caused by hot air/liquid rising and cold air/liquid falling.
• Radiation is the transfer of heat by electromagnetic radiation, specifically infra-red radiation.
• When an object absorbs heat it does not necessarily change temperature. As objects change state they do not change temperature. The heat that goes into something as it’s changing phases is used to change the “bonds” between molecules. Freezing points, melting points, boiling points and condensation points are the “speed limits” of the phases. Once the molecules reach that speed they must change state.
• Objects release heat as they freeze and condense. Objects absorb heat as they evaporate and melt.
• Heat capacity is how much heat an object can absorb before its temperature increases.
• Specific heat is how much heat energy a mass of a material must absorb before it increases 1°C.
• Each material has its own specific heat. The higher a material’s specific heat is, the more heat it must absorb before its temperature increases. Water has a very high heat capacity.

Yay! You’ve completed the lessons in Thermodynamics! Now it’s time to try your own problem set.

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