Term | Definition |
Chemistry | study of composition, structure, properties, and reactions of matter |
Matter | all substances that make up our world--anything that has mass and occupies space
and is either pure substances or mixtures |
Chemicals | substances that have the same composition and properties wherever found |
Scientific Method | set of general principles that help to describe how scientists think |
Steps of the Scientific Method | Make Observations
Propose a Hypothesis
Conduct Experiments
Form a Conclusion |
What are the two parts of the scientific notation? | coefficient and power of 10 |
Units of Measurement in Metric | length: m
volume: L
mass: g
Temp: Celsius
Time: s |
Units of Measurement in SI | length: m
volume: m^3
mass: kg
Temp: K
time: s |
1m | 100 cm |
1L | 1000mL |
1kg | 1000g |
Measured Numbers | numbers obtained when you measure a quantity such as your height, weight, or temperature
-observe the numerical values of marked lines
-estimate value of the numbers between marks
-use the estimated number as the final number in your measured numbered |
Significant Figures | -used to represent the amount of error associated w a measurement
-all nonzero digits and zeros between digits
-zeros at the end of a decimal number |
Exact Numbers | are in definitions that compare two units in the same measuring system |
Multiplication and Division---Sig Figs | final answer is written so that it has the same number of sig figs as the measurement w the fewest sig figs |
Adding and Subtracting--Sig Figs | final answer is written so that it has the same number of DECIMAL places as the measurement w the fewest decimal places |
Equalities | use two different units to describe the same measured amount |
Density | compares the mass of an object to its volume
DENSITY=MASS OF A SUBSTANCE/VOLUME OF A SUBSTANCE |
pure substances | have a fixed or definite composition
an element that is composed of one type of atom
a compound that is composed of two or more elements always combined in the same proportion |
mixtures | contain two or more different substance that are physically mixed but not chemically combined |
elements | pure substances that contain only one type of material |
compound | contains two or more elements in a definite ratio |