Chapter 4 Definition
What is used to measure temperature?
A Thermometer.
What is the most common temperature scale used in the US?
Fahrenheit Scale- water freezes at 32 degrees and boils at 212 degrees. There are 180 degrees between freezing and boiling point. Developed by Gabriel Fahrenheit.
What are expansion joints?
Sidewalks, driveways, highways and bridges are built with breaks or gaps to allow for thermal expansion. These expansion joints allow the material to expand or contract safely.
Temperature
Measures the average KE of particles in an object or substance.
Temperature
The measure of the average KE of all of the particles in an object.
What happens to particles when temperature increases?
The particles are moving more quickly.
High Specific Heat Value
A substance with a high specific heat value, like water, has to absorb a large amount of energy to raise its temperature by 1 degree Celcius. If you absorb a large amount of energy to increase your temperature, you have to RELEASE a large quantity of energy for your temperature to decrease.
How does a thermometer work?
A thermometer works because the liquid in it (alcohol or mercury) expands or contracts by a certain amount as the temperature changes.
What unit is temperature measured in?
Degrees
Do particles always move at the same speed?
No. Particles do not always move at the same speed. Particles have a wide range of speeds and often change speeds.
Are heat and temperature the same?
No. Heat is different from temperature. They are often confused because they are closely related
How do electrical thermometers work?
Some thermometers work by using a material whose electrical properties change as the temperature changes. These thermometers are read by computers and who the temperature on a display panel.
What does kinetic energy depend on?
Speed of particles. Particles of matter moving at different speeds have different amounts of KE because KE depends on speed.
The Kinetic Theory of Matter
State thats all particles that make up matter are constantly in motion. This helps to explain the different states of matter.
What does the temperature scales depend on?
The freezing point of water and the boiling point of water. The degrees are evenly spaced between these 2 points.
Do some substances change temperatures more easily than others?
Yes.
What are the 2 most common units used to measure heat?
1) calorie 2) joule
What is the temperature scale used most commonly in science and the world?
Celsius Scale - water freezes at 0 degrees and boils at 100 degrees. There are 100 degrees between freezing and boiling point. Developed by Anders Celsius.
How does energy transfer?
Heat energy is always transferred from an object with a higher temperature to an object with a lower temperature until both reach the same temperature.
What is Thermal Expansion?
How a material expands or contracts as the temperature changes.
What happens to thermal energy in a transfer of heat energy?
In a transfer of heat energy, the thermal energy of the objects will change, the object with the warmer temperature will loose thermal energy as it transfers its heat energy to the cooler temperature object. The cooler temperature object will gain thermal energy as its temperature increases.
Specific Heat
Is the amount of energy needed to raise the temperature of 1 gram of a substance by 1 degree Celcius.
What does all matter have?
Kinetic energy. All matter is made up of atoms and atoms are always in motion.
What does kinetic energy depend on?
Mass and speed. So, an object with more mass can be the same temperature with slower moving particles than an object with less mass and a particles moving faster with higher speed.
Thermal Energy
The TOTAL random KE of particles in an object.
It is impossible to know the kinetic energy of each particle in a substance. But, the ________ can be measured?
The average kinetic energy of all the particles in a substance can be measured.
What is equilibrium?
When both objects have reached the same temperature. Eventually in a heat transfer, both objects temperatures will eventually be the same.
How does thermal energy the objects change?
When energy flows from a warmer object to a cooler object, while the objects temperatures are reaching an equilibrium, the thermal energy of both the objects change.
Does each substance have its own specific heat value?
Yes. Every substance has its own specific heat value. So, each substance absorbs a different amount of energy to show the same increase in temperature.
Heat
flow of energy from an object with a higher temperature to an object with a lower temperature.
