Chapter 1 Flashcards
History of chemistry
Early alchemists known as “chemists”
Early study of alchemy
Metals–> gold
Chemistry
Scientific study of matter & How it changes
Scientific Method
Ask questions about the natural world
- Ask a question
- Background research
- Hypothesis
- Experiment
- make observation or test hypothesis
- Gather data
- Conclusion
Significant figure rules
- all Non-zero digits are significant (123456789)
- All zeros between non zeros are significant (2002)
- All beginning zeros are NOT sig (002)
- Ending zeros are only significant if decimal is present (20.870)
Density
D= m/v
- comparing mass of object relative to size
- gas is less dense than liquids & solids
Mass formula
M=DxV
Volume formula
V=M/D
Accuracy
How close the measured value is to the actual value
Quality effects it
Precision
How close the values in a set of measurements are to each other
Percent error
Accepted value - experimental value
_________________________________ x 100
Accepted value
SI (system of measurement): length
Inch
Foot
Yard
Mile
SI: volume
Cup
Teaspoon
Quart
Gallon
Length base unit
Meter
Mass base unit
Grams
Temperature base unit
Celsius
Time base unit
Seconds
Volume base unit
Liters
Prefixes (kilo, Hecto, deka, deci, centi, milli)
Kilo: 1000xbase Hecto:100xbase Deca: 10xbase Deci: tenth x base Centi: hundredths of base Milli: thousandth of base
Mass definition
The amount of matter (unchanging)
Volume definition
Amount of space occupied by matter
Temperature
A measure of the average kinetic energy
: C= k - 273
Equation to find Celsius
C = K - 273
