Mr. Fleming
D.1 What are the effects adding energy to matter in terms of the motion of atoms and molecules, and the resulting phase changes?
All of the physical ‘stuff’ around us Solids, Liquids, Gases What are some examples of matter? ◦ Rocks ◦ Air ◦ Trees
The smallest building blocks of matter All matter is composed of one or more atoms They cannot be created or destroyed, but simply change form Composed of three particles: Protons, Neutrons and Electrons
Blue: Protons (positive charge +1) Red: Neutrons (neutral charge) Black: Electrons (negative charge -1)
Atoms can combine to form complex molecules, which make up all matter. They combine via their electrons, which try to fill up all of the available spaces the atom can hold. The many different ways that atoms combine form the multitude of different kinds of matter we find on Earth.
Study of how energy in the form of heat is transferred to various types of energy within a system. Defined by laws
Conservation of Energy Energy can neither be created nor destroyed only transferred between different types of energy.
The ability to do work or make things move. Many different types of energy
Heat- the total kinetic energy of the particles that make up a substance. Units- joules or calories (cal) When you add heat to an object, you are adding energy to that object. The increase in kinetic energy causes the object to expand. Heat flows from warmer to cooler materials.
Contraction ◦ Lose Heat=atoms/molecules come together Expansion ◦ Gain Heat=atoms/molecules move further apart
What is heat a measure of? The total amount of kinetic energy of the particles that make up a substance. What happens to the speed of the particles in a substance as heat is taken away? Slow Down
Matter is made of particles (atoms and molecules). These particles are constantly in motion. The speed that these particles are moving determines the temperature of an object. Temperature- a measure of the average kinetic energy of the particles in an object.
Three Scales: Fahrenheit (˚F) Celsius (˚C) Kelvin (K)- Absolute zero Conversion Formulas: ˚C = (˚F - 32) x 5/9 ˚F = (C x 1.8) + 32 ˚K=(F )
Heat ◦ Total Amount of Kinetic Energy Temperature ◦ Average Amount of Kinetic Energy
Beaker A and B have equal volumes. Beaker A has particles moving faster than Beaker B. Which beaker has the higher temperature? Beaker A Which beaker contains more heat? Beaker A
Why does it get easier to open a jar when you add hot water to lid? Particles expand when heat is added to it. Metal in lid expands causing it to loosen from jar.
Are heat and temperature the same measurement? Explain. No, temperature is the average amount of kinetic energy and heat is the total amount of kinetic energy.
Specific Heat- the amount of heat that is needed to raise the temperature of 1kg of a material by 1˚C. This measurement determines how things conduct heat. Example- Plastic has a higher specific heat than metal which is why we use plastic spoons when we cook.
Specific Heat Demo
Heat – the total KE of a material. Temperature – the average KE of a material. Specific Heat - the amount of heat that is needed to raise the temperature of 1kg of a material by 1˚C.
True or False: For any two objects, the one with the higher temperature always has more thermal energy. False, glass could have higher temperature than pool, but pool will have higher thermal energy.
Describe how the thermal energy of an object changes when the object’s temperature changes. Thermal energy increases along with temperature of object.
When heat flows between two objects, does the temperature increase of one object equal the temperature decrease of the other? No, heat could be lost to air surrounding object.