fractions that represent the same unit (where the numerator and the denominator are equal to each other) ex. 100 cents/1 dollar
How are conversion factors used?
used to solve any kind of problem
International System of Units
the revised version of the metric system, adopted by international agreement in 1960 The five SI base units commonly used by chemists are the meter, the kilogram, the kelvin, the second, and the mole.
a force that measures the pull on a given mass by gravity. It is a measure of force, it's different from mass, which is a measure of the quantity of matter.
the freezing point of water is 273.15 kelvins (K), and the boiling point is 373.15 K. Notice that with the Kelvin scale, the degree sign is not used. The zero point on the Kelvinscale, 0 K, or absolute zero, is equal to −273.15°C.
the capacity to do work or to produce heat
the SI unit of energy. It is named after the English physicist James Prescott Joule
One of these is the quantity of heat that raises the temperature of 1 g of pure water by 1°C
a way to analyze and solve problems using the units, or dimensions, of the measurements. The best way to explain this problem-solving technique is to use it to solve an everyday situation.
the ratio of the mass of an object to its volume. densisty= mass/volume
a quantity that has both a number and a unit, fundamental to the experimental sciences
a given number is written as the product if two numbers: a coefficent and 10 raised to a power
a measure of how close a measurement comes to the actual or true value of whatever is measured
a measure of how close a series of measurments are to one another
To evaluate accuracy...
measured value compared to the correct value
To evaluate precision...
compare the values of two or more repeated measurments
the correct value based on reliable references
the value measured in the lab
the difference between the experimental value and the accepted value Error= experimental value - accepted value
The absolute value of the error divided by the accepted value, multiplied by 100 % error= |error| / accepted value x 100