1. Chapter 2: Energy and Matter

3. Measuring Energy
calorie – the amount of heat required to raise the temperature of 1 gram of water 1 degree C.
4.184J = 1cal
Calorie (food) = 1000 calories

4. The point at which the motion of particles ceases K = 273 + C
Measuring energy
Kelvin – based on absolute zero
The point at which the motion of particles ceases
K = C
C = K - 273

5. Matter Matter – anything that has mass and volume
Solid – definite mass and volume
Liquid – definite volume, no definite shape
Gas – no definite shape or volume

6. Ex. Density, color, mp, bp, crystalline shape and conductivity
Properties of Matter
Physical Properties – Can be observed without changing the identity.
Ex. Density, color, mp, bp, crystalline shape and conductivity

7. Ex. Flammability, ability to rust
Properties of Matter
Chemical Properties – Have to change the substance to observe
Ex. Flammability, ability to rust

8. Ex. Breaking glass, melting butter
Changes
Physical Change – does not alter the substance
Ex. Breaking glass, melting butter
Chemical Change – Changes that alter the substance.
Baking a cake, iron rusting

9. Law of Conservation of Matter
Matter cannot be created nor destroyed, it just changes form.
Ex. K + C  KC
If I have 2.4g of K and 3.6g of C how many g of KC would I have?
6.0g

10. Energy
Energy is the capacity to do work
Potential Energy- stored energy
Kinetic Energy – energy of motion

11. Elements, compounds, mixtures
Element – a substance that cannot be separated into simpler substances by chemical means.
Found on the periodic table.
Compound – substance that contains 2 or more elements, chemically combined in fixed proportions.

12. Elements, compounds, mixtures
Mixture- Blend of 2 or more pure substances
Substances retain their own properties
Separated by physical means
Filtration, distillation

13. solutions Homogeneous solutions – no visibly different parts
Ex. Salt water, air
Heterogeneous Mixture – Visibly different parts
Chocolate chip cookies