1. Chap 1,2&3 Review
Honors Chemistry

2. Nature of Science
Attempt to explain the Natural occurring phenomena of the Universe by logical means.
Study of Matter and Energy is The Science of Chemistry

3. Rules for assigning significance to a digit:
1. Digits other than zero are always significant.
2. Rules about zeros:
a. Final zeros after a decimal point are always significant.
b. Zeros between two other significant digits are always significant.
c. Zeros used only to space the decimal are never significant.

4. Significant Digits Multiply/Division- Least number of Digits
g / 8.7 cm3
2 digits in the answer
2.7 g/cm3
Addition/Subtraction- Least number of Decimal Places
g g g
1 decimal place in the answer
60.5 g

5. SI Units Mass- Kilogram - kg Time- Second- s Length- Meter - m
Electric Current- Ampere- A
Temperature- Kelvin - K
Amount of substance - mole - mol

7. Conversion Bar n u m c d base da h k M G T

8. Precision vs. Accuracy
Precision- how close a set of measurements are to each other, all within acceptable degree of uncertainty
Determined by the individual
Accuracy - How close a measurement is to the objects true value
Determined by the measuring instrument

10. Matter and Energy Different sides of the same coin
Matter- the substance of the universe
Energy- the capacity to do work
Potential energy - stored energy
Chemical Energy is stored in chemical bonds
Kinetic energy - energy of motion

11. Heat
The sum total of kinetic energy, KE, of the particles in a sample of matter
Average KE ~ Temperature

12. Endothermic and Exothermic
Endothermic - energy is absorbed during a chemical or physical change
Feels cold
Example
Physical - melting ice
Chemical - cold pack
Exothermic - energy is released during a chemical or physical change
Feels Hot
Physical - making ice
Chemical - Iron changing to rust

13. Mass vs. Weight Mass amount of matter in a substance
Amount of matter in an object is constant
Weight amount of force on a substance
Force can change the weight but not the amount of matter

14. Properties of Matter
Chemical Properties - change the substance, can not be reversed by physical means
Physical Properties - change the appearance or state of the substance and can be reversed by physical means

15. Properties of Matter Examples of Chemical Change
Produces heat or light
Produces new substance
Examples of Physical Change
Change in state of matter
Changes in physical size or shape

16. Intensive vs. Extensive Properties
Intensive Properties DO NOT depend on the amount of matter in a substance
Density
Extensive Properties Do depend on the amount of matter in a substance
Mass or volume

17. States of Matter Solid Liquid Gas Plasma Volume and shape
Minimal molecular kinetic energy
Liquid
Volume , no shape
Moderate molecular kinetic energy
Gas
No volume or shape
Maximum kinetic energy
Plasma
Striped of electrons found in stars or star like conditions

18. Mixtures Mixtures can be separated by physical means
I.e. Distillation, Screening, Gravity
Homogeneous Mixture
Consist of solute and solvent
Appears to be a single substance
Heterogeneous Mixture
Phases can be distinguished

19. Pure Substances Consists of one type of substance Element Compound
A single type of matter
Compound
A mixture of elements in a definite ratio
Water is 2 parts hydrogen to one part oxygen, H2O, everywhere in the Universe

20. Scientific Method Observation Hypothesis Experimentation
New Hypothesis
Theory
Law

21. Observation Observance of natural occurring phenomena A Fact
Qualitative
Non-numerical description
Subjective
Quantitative
Numerical Description
Objective

22. Hypothesis The best explanation of a natural occurring phenomenon
Testable
Falsifiable
States observation (if) and makes prediction (then)

23. A model Theory Verbal, mathematical or computer generated
A set of tested Hypothesis that provides an overall explanation of a natural occurring phenomena
A model
Verbal, mathematical or computer generated

24. Law A measurable summary of natural occurring phenomena
General Summary of Universal Events

25. Density
Measurement of mass per unit volume (space)
D=m/v