Scientific Endeavour Flashcards
Define accuracy.
Accuracy is when a reading is very close to the true value of the quantity when making a measurement.
Define precision.
Precision is when multiple readings that are taken are very close to one another or are the same.
What is qualitative data? List 2 examples.
Qualitative data is observations made using our senses.
Senses:
Sight, Hearing, Touch, Smell, Taste.
What is quantitative data?
Quantitative data is measurements of numerical quantities of an object or phenomenon. (Things that CAN be counted)
What is a zero error?
Zero error is a type of error when an instrument gives a non-zero reading when the measured quantity should be a zero. ( It is consistent. -> systematic error )
What is a parallax error?
Parallax error is introduced into a measurement when the marking on an instrument is viewed from the wrong angle. ( It is consistent. -> systematic error )
How does a strike back in a Bunsen burner occur?
It occurs when there is too much air, specifically oxygen, entering the air-hole.
Give 2 differences between luminous and non-luminous flame.
A non-luminous flame occurs when the air-hole is opened whereas the luminous flame occurs when the air-hole is closed.
OR
A non-luminous flame burns steadily whereas a luminous flame burns unsteadily.
OR
A non-luminous flame is hotter than the luminous flame.
OR
A non-luminous flame has an outer blue flame whereas a luminous flame has an outer orange flame.
What is an independent variable? ( Changed Variable )
It is the variable that you change during an experiment.
- There should only be one independent variable in your experiment.
What is a dependent variable? ( Measured Variable )
It is the variable you observe and record during your experiment.
What is a controlled variable? ( Constant Variable )
A variable that is needed to remain constant to ensure a fair test.
( there can be multiple controlled variables. )
What is the S.I. Unit for mass? And what is an apparatus used to measure mass?
Kilogram. We can measure the mass of a substance using an electronic balance.
What is the S.I. Unit for time? And what is an apparatus used to measure it?
Seconds (S) . Stopwatch.
What is the S.I. Unit for volume? And what apparatus can you use to measure it?
Cubic metres (m 3). Measuring cylinder.
What is the S.I. Unit for Temperature? And what is an apparatus used to measure it?
Kelvin (K). A laboratory thermometer.
What is the S.I. Unit for length? And what is an apparatus used to measure it?
Metres (M) . Ruler/caliper.
How do you remove the zero error when using an electronic balance? (To measure mass.)
By pressing the tare function to reset the digital display to zero before weighing.
How do you read the volume of a liquid accurately and precisely?
By aligning your eyes to the liquid level to prevent parallax error.
Concave meniscus -> Read off the scale at the BOTTOM of the meniscus.
Convex meniscus -> Read off the scale at the TOP of the meniscus.
How do you read the temperature of something by using a thermometer?
You must read it at eye level to prevent parallax error and the bulb of the thermometer must be fully submerged.
What is the scientific process?
- Investigation
- Evaluation and reasoning
- Developing explanations and solutions.
