10/23/2011

### Conversion factors

fractions that represent the same unit (where the numerator and the denominator are equal to each other)

ex. 100 cents/1 dollar

### 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.

### Weight

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.

### Kelvin Scale

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.

### calorie (cal)

One of these is the quantity of heat that raises the temperature of 1 g of pure water by 1°C

### Dimensional Analysis

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.

### scientific notation

a given number is written as the product if two numbers: a coefficent and 10 raised to a power

### Accuracy

a measure of how close a measurement comes to the actual or true value of whatever is measured

### Error

the difference between the experimental value and the accepted value

Error= experimental value - accepted value

### Percent Error

The absolute value of the error divided by the accepted value, multiplied by 100

% error= |error| / accepted value x 100