Scientific measurements almost exclusively use the metric system. Each variable - mass, length, time, has a base unit in which everything is measured. They are then given prefixes to make the numbers easier to work with in calculations or conversation.

Name

Symbol

Scientific Notation

Adjustment Factor

exa

E

1018

1,000,000,000,000,000,000

peta

P

1015

1,000,000,000,000,000

tera

T

1012

1,000,000,000,000

giga

G

109

1,000,000,000

mega

M

106

1,000,000

kilo

k

103

1,000

hecto

h

102

100

deka

da

101

1

deci

d

10-1

.1

centi

c

10-2

.01

milli

m

10-3

.001

micro

ų

10-6

.000001

nano

n

10-9

.000000001

pico

p

10-12

.000000000001

femto

f

10-15

.000000000000001

atto

a

10-18

.000000000000000001

Mass - The base unit of measurement in Canada is the gram. This is about the weight of a dime. If we had 1000 dimes, it would weigh 1 kg.

Likewise, it we had 1 gram of mercury, we would have 1000 mg, or 1,000,000 ųg of mercury.

Volume - The base unit of measurement of volume in Canada is the litre.

If we had one litre of water, we would have 1000 mL.

Likewise, if we had 1 mL of water, we would have .001 L of water.

Concentration - A concentration is the relationship between the amount of a substance you have, and the space you're fitting it into. For materials dissolved in water, the concentration is usually given as mg/L, but many other systems exist.

To draw an example from the Health Canada guidelines for water contaminants, the Maximum Allowable Concentration for mercury is 0.001 mg/L. This means that for every litre of water, there should be no more than 0.001 mg, or 0.000001 grams of mercury.

More concentration - Another common form of expressing concentration is parts-per-million (ppm) or parts-per-billion (ppb). Unlike mg/L, however, ppm and ppb are relationships between the two things, usually the solute and the solvent, rather than an explicit value.

A 1 ppm concentration of sugar in your coffee would mean that there is one sugar molecule for every million coffee "molecules".

For trivia night, the lowest concentration at which most people can taste chlorine in their water is 0.156 ppm.

## Units of Measurement and Terminology

## Units of Measurement

Scientific measurements almost exclusively use the metric system. Each variable - mass, length, time, has a base unit in which everything is measured. They are then given prefixes to make the numbers easier to work with in calculations or conversation.

NameSymbolScientific NotationAdjustment FactorMass- The base unit of measurement in Canada is the gram. This is about the weight of a dime. If we had 1000 dimes, it would weigh 1 kg.Likewise, it we had 1 gram of mercury, we would have 1000 mg, or 1,000,000 ųg of mercury.

Volume -The base unit of measurement of volume in Canada is the litre.If we had one litre of water, we would have 1000 mL.

Likewise, if we had 1 mL of water, we would have .001 L of water.

Concentration -A concentration is the relationship between the amount of a substance you have, and the space you're fitting it into. For materials dissolved in water, the concentration is usually given as mg/L, but many other systems exist.To draw an example from the Health Canada guidelines for water contaminants, the Maximum Allowable Concentration for mercury is 0.001 mg/L. This means that for every litre of water, there should be no more than 0.001 mg, or 0.000001 grams of mercury.

More concentration- Another common form of expressing concentration is parts-per-million (ppm) or parts-per-billion (ppb). Unlike mg/L, however, ppm and ppb are relationships between the two things, usually the solute and the solvent, rather than an explicit value.A 1 ppm concentration of sugar in your coffee would mean that there is one sugar molecule for every million coffee "molecules".

For trivia night, the lowest concentration at which most people can taste chlorine in their water is 0.156 ppm.