Chemistry
Vocabulary Chapter 2
1. Base Unit: A defined unit in a system of measurement that is based on an object
2. Density: The amount of mass per unit volume. It is a physical property
3. Derived Unit: A unit defined by a combination of base units.
4. Kelvin: The SI base unit of temperature.
5. Kilogram: The SI base unit for mass; about 2.2 lbs
6. Liter: The metric unit for volume equal to one cubic decimeter.
7. Meter: The Si base unit for length
8. Second: The SI base unit for time
9. Conversion factor: A ratio of equivalent values used to express the same quantity
in different units. It is always equal to 1 and changes the units of a quantity
without changing its value.
10. Dimensional analysis: A systematic approach to problem solving that uses
conversion factors to move from unit to another
11. Scientific Notation: Expresses any number as a number between 1 and 10
multiplied by 10 raised to a power.
12. Accuracy: Refers to how close a measured value is to an accepted value
13. Error: The difference between an experimental value and an accepted value
14. Percent error: The ratio of an error to an accepted value.
15. Precision: Refers to how close a series of measurements are to one another.
Precise measurements show little variation over a series of trials but might not be
accurate.
16. Significant figure: the number of all known digits reported in measurements plus
one estimated digit.
17. Graph: A visual display of data