Scientific Endeavour Flashcards
(39 cards)
What is independent variable?
changed variable
What is dependent variable
measured variable
Which is not an appropriate way of recording a scientific observation?
A. The solid turns blue when heated
B. The solid gives off a gas when heated
C. The solid is affected by heat
D. The solid melts when heated
C
What is the SI unit for volume
m3 ( cubic metre )
What is the SI unit for mass
Kg ( kilogram )
What is SI unit for time
S ( seconds )
What is the SI unit for length
m ( metre )
What is the S! unit for temperature
K ( kelvin )
What is accuracy
Accuracy is when a reading is very close to or same as the true value , the measurement is said to be accurate
What is zero error
Zero error is when an instrument gives a non-zero reading when the measured quantity should be zero
What is parallax ( do not spell it wrongly ) error
Parallax error is when the marking on an instrument is viewed from the wrong angle during a measurement
How to avoid parallax error when looking at the ruler
Position the eye so that the line of sight is perpendicular to the marking on the ruler
How to avoid parallax error when looking at measuring cylinder
Position the eye so that the line of sight is level with the bottom of the meniscus
What is accuracy
” The measured value is close to the actual value “
What is precision
” Closeness of the measured value “
Why do we need to wear safety goggles
To protect the eyes from chemicals
Why do wee place flammable substance away from the naked flame
To prevent fire
Why do we need to point mouth of test tube away from anyone when heating
To prevent burning from heated substance that spills out
why do we not eat, drink and play in the laboratory
To prevent swallowing, knocking and spilling of chemicals
Why do we dispose used and unused chemicals properly
Unused chemical poured back into its container causes contamination ( dangerous chemicals must be disposed off in correct manner)
Why to not taste any chemicals
Most chemicals are poisonous
Why to not tamper with electrical mains and other fittings in lab
To avoid electrical hazard
Why do we report damaged equiment, breakages, accidents and spilllage to teacher immediately
To avoid accidents and danger
Use for test tube and boiling tube
holding small saple or for containing small-scale reactions
