1. Chapter 1 Matter and Measurement
Honors Chemistry
Chapter 1
Matter and Measurement

2. 1.1 The Study of Chemistry
Chemistry: The study of matter and the changes it undergoes
Matter anything that has mass and occupies space ( has volume)
Atoms: the building blocks of matter
Elements: pure substances that contain identical atoms
Molecules: combinations of atoms

3. 1.1 Why study Chemistry?
Chemistry is called the central science because it overlaps all the other sciences
Chemistry tells us how and why our world works

4. 1.2 Classifications of Matter
Two ways that matter is usually classified
Physical state
Solid, liquid, gas, plasma
Composition
Element, compound, mixture
A pure substance is matter that has a fixed composition and distinct properties

5. 1.2 Classifications Of Matter
Pure Substances can be classified as either elements or compounds
Elements are pure substances that cannot be broken down into simpler substances
Compounds: combinations of two or more elements, can be broken down chemically to the base elements

6. 1.2 Classifications of Matter
Mixtures are combination of two or more substances that are not chemically combined, can be separated by physical means, and it substance retains it chemical identity and properties
Heterogeneous Mixtures: non-uniform
Homogeneous Mixtures: uniform and consistent
Solutions are Homogeneous Mixtures

7. 1.2 Classification of Matter
We can separate a mixture by taking advantage of the physical properties of the components in the mixture
Elements
There are 112 known elements
Listed in periodic table using chemical symbols

8. 1.2 Classification of Matter
Compounds are combinations of elements
Always for in whole number ratios of elements
Law Of Constant Composition: compounds are formed by the whole number ratio combination of elements, the formulas for these compounds are always the same

9. 1.3 Properties of Matter
Physical Properties: can be observed or measured without changing the chemical composition of the substance
Chemical Properties: how substances react to other substances, to observe, the chemical composition usually changes
E.g. flammability

10. 1.3 Properties of Matter
Physical Change: a change in appearance, no change in the chemical composition
Change in state
Chemical Changes: a substance is changed into a new substance with different chemical properties

11. 1.3 Properties of Matter
The Scientific method: organized way to solve problems
Steps
1. Define a problem
2. Form hypothesis
3. Experiment, collect data
4. Theorize
5. Publish Results

12. 1.4 Units of Measurement Quantitative: related to numbers
Qualitative: descriptions, attributes
The units of acceptable measurements in all science is the metric system
Consistent Measurement allows scientists to communicate their results
“SI” system of Measurement

13. 1.4 Units of Measurement 7 Base Units in SI 1. Length…………meter
2. Mass…………..kilogram
3. Time…………..second
4. Quantity……….mole
5. Temperature…..Kelvin
6. Electric Current….ampere
7. Luminous Intensity….candela

14. 1.4 Units of Measurement Derived units are combinations of base units
Volume, density, force, pressure

15. 1.5 Uncertainty in Measurement
Numbers are exact or inexact
All measurements contain some error
1. The instrument
2. Usually involve estimation
Precision: How well a piece of equipment makes a consistent measurement
Accuracy: how close the measurement is to an accepted value

16. 1.5 Uncertainty In Measurement
Significant Figures all numbers known in a measurement that are exact plus one estimated digit that is inexact (estimate)
Rules:
1. Nonzero digits are always significant
2. Zeros between nonzero digits are always significant
3. Zeros at the beginning of numbers are never significant
4. Zeros at the end of a number to the right of a decimal are significant
5. Zeros at the end of a number with no decimal are not significant

17. 1.5 Uncertainty in Measurement
Significant Figure Calculations
Addition and Subtraction: the result can not have more digits to the right of the decimal than any of the original numbers
Multiplication and Division: the result must be reported with the same number of significant figures as the the measurement with the fewest significant figures
The weakest link

18. 1.6 Dimensional Analysis Units are treated as algebraic quantities
Solve for the units, if it gives the correct units in the answer, the problem will most likely be correct
Conversion factors are used to change a number from one system of measurement to another
Numbers without units are worthless