Problem Solving & Exam Technique Flashcards
How do you calculate a percentage change?
difference/original x 100%
If the question asks, ‘what is the difference between’…?
you must mention BOTH e.g difference between diffusion and active transport - active transport requires energy is not enough MUST mention diffusion does not require energy.
If the question asks, ‘calculate the average’…what do you do?
the total/the number of numbers you added together
If the question asks, ‘calculate the average change’…what do you do?
total change/ time
BUM?
Box the command word
Underline the key terms
Marks - how many is it worth? Have I done enough?
If the question asks you to ‘describe’…what should you do?
As much detail as you can give.
The police have asked for a description of the person that stole your bike, you would not describe them as ‘man’.
If the question asks you to ‘explain’…what should you do?
Tell me WHY
What should you do if you have a graph with 2 lines?
Colour them in with 2 different colours
How do you read a graph accurately?
Use a ruler
What should you do if you see the word ‘reliable’ in a question?
Mention what exactly you are REPEATING and then calculate an average
If the question asks for ‘percentage increase’…?
difference/original x 100%
If the question asks for a ‘percentage decrease’…?
difference/original x 100%
What is an independent variable?
The one thing that has been changed by the scientist in the experiment
What is a dependent variable?
The thing that is measured to get the results in an experiment.
Am*unt?
Don’t you swear at me! DO NOT use this term in your answer instead use volume, mass, size
It?
NEVER use ‘it’ in your answer instead of the correct name. You say ‘it’, I say ‘what?’
What is a ‘control’?
They prove that the variable being investigated is responsible for the result. Common examples include glass beads instead of living organisms and water in place of solutions.
2 reasons why an experiment may be left for a period of time before measurements are taken?
- allow living organisms to acclimatise to new conditions
- allow apparatus to stabalise
- allow osmosis/diffusion to happen
- allow solutions to reach desired temperatures
Why are percentage changes sometimes calculated in results tables?
If the starting figures were different it allows a comparison to be made.
How would you predict a result from a line graph?
use a ruler to extend the existing line
If a questions asks you to ‘Using data from the graph, describe’…what should you do? (not a trick question!)
Guess what, USE DATA FROM THE GRAPH!!! NUMBERS in your description
What does DRAW a conclusion NOT mean?
Draw a picture
Is a question asks you to ‘draw a conclusion’, what should you do?
- Look at the aim and answer that
- Mention the independent and dependent variables in your answer (the dependent variable might not be what is stated in the table/graph - look at the aim!!!)
What should you do if the question asks you to ‘state variables that must be kept constant’?
Read the experiment carefully and decide which variables NOT mentioned already that would need to be kept the same to make it fair.
3 possible examples of variables that must be kept the same?
temperature volumes concentrations mass surface area diameter of samples thickness of samples time pH
What is never the correct answer for a variable that must be kept the same?
Am*unt - never use this word! It is swearing.
Which variable always goes on the bottom of a graph?
The independent variable
What should you do if the question asks you ‘how many times greater’ is X than Y?
Divide the big number by the small number
How do you calculate the ‘average increase’?
total change/ time
How do you calculate the average decrease?
total change/ time
How do you calculate a simple whole number ratio?
Divide all of the numbers in the ratio by the same number until they cannot be divided any more.
5 steps to answering questions about a passage of text.
- Read the text
- Highlight key word in question
- Scan ands highlight key word in the passage
- Read the sentences around the key word
- Your answer can be copied directly from the passage - you do not need to put it in your own words
How do you calculate what each small square is worth on the scale of a graph?
the increase in number between the big lines/number of small squares
