Ex 3 Measurements And SI Units Flashcards
All scientific experiments are based on
Measurements and calculations made from these measurements
In _____, a major step was taken to consolidate and simplify measurements when the ____________ adopted the __________
1960
General conference of weights measure
International system of units
Logical extension of the metric system that relates all units of measurements to the fewest possible base units
International system of units (SI units)
Seven SI Base units
Length - meter (m)
Mass - kilogram (kg)
Time - second (s)
Electric current - ampere (A)
Thermodynamic temp. - Kelvin (K)
Amount of substance - mole (mol)
Luminous intensity - candela (cd)
Unit which can be computed by dividing mass by volume
Density
The mass of an object is commonly measured in
Balance
Most common of which are the
Double pan or single pan balances
Can be measured more familiarly with a graduated cylinder but more accurately with a pipette or burette
Volume of liquid
In measuring the ________, a ______solid like a cube can have its volume calculated from its measured dimensions (V= LxWxH)
Volume of a solid
Regularly shaped
If the solid is ________, its volume is taken directly
Irregularly shaped
When reading the volume of liquids, place the container in a flat surface with the liquid surface at _____
Eye level
The concave surface
Meniscus
The reading is taken at the ____ of the meniscus
Bottom
For dark solutions, the ____ of the meniscus is read
Upper edge
A balance that is commonly used for beginners
Triple beam balance
This does not have an accessory set of weights like the more sensitive ones
Triple beam balance
Achieved by simply sliding and positioning the rider weights on the notches along the three beam until the pointer at the extreme right makes equidistant swing above and below the zero point
Balancing
