Chem 1048A
BHSc
Learning Goal 2:
Measurement & Units
(Attendance at lectures is necessary to complete these notes)
Ms Brankin
Office 303
(011) 717-6729
, Units of Measurement
Any measurement consists of 3 interlinked concepts:
a measured number
a unit
a measure of the uncertainty
If you repeat a particular measurement, you usually
do not obtain precisely the same result, because
each measurement is subject to experimental error.
, SI Base Units & SI Prefixes
• All scientific units use Système International
d’Unités (SI Units).
• The International System or SI was adopted in
1960 and is a particular choice of metric units.
• There are seven base units from which all
other units can be derived.
• In SI a larger or a smaller unit for a physical
quantity is indicated by a SI prefix.
, SI Base Units
There are 7 base units in the SI system
Important: the liter is not an SI unit.
BHSc
Learning Goal 2:
Measurement & Units
(Attendance at lectures is necessary to complete these notes)
Ms Brankin
Office 303
(011) 717-6729
, Units of Measurement
Any measurement consists of 3 interlinked concepts:
a measured number
a unit
a measure of the uncertainty
If you repeat a particular measurement, you usually
do not obtain precisely the same result, because
each measurement is subject to experimental error.
, SI Base Units & SI Prefixes
• All scientific units use Système International
d’Unités (SI Units).
• The International System or SI was adopted in
1960 and is a particular choice of metric units.
• There are seven base units from which all
other units can be derived.
• In SI a larger or a smaller unit for a physical
quantity is indicated by a SI prefix.
, SI Base Units
There are 7 base units in the SI system
Important: the liter is not an SI unit.
