Module 1.1 Practical skills assessed in a written assessment Flashcards Preview

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Flashcards in Module 1.1 Practical skills assessed in a written assessment Deck (43)
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1

Primary research

New data is collected and conclusions are then drawn

2

Secondary research

Data from other studies is used to draw conclusions

3

Valid results

Are suitable results that can test the aim

4

Hypothesis

A prediction using scientific knowledge and trusted information from textbooks, colleagues and papers

5

Surveys

A type of primary research

Sets out limits to observe something already happening

6

Meta study

Secondary research

Uses the raw data from a variety of different studies to try to answer a new aim

Mathematical approach using statistics

Allows a large data group to be studied

7

Quantitative data

Has a numerical value

Requires a measuring instrument to be observed

8

Qualitative data

Descriptions of what is observed

9

Resolution

The smallest change in the quantity being measure that can be observed

10

Accuracy

How close to the true value a measurement is

11

Independent variable

The factor that you are interested in changing to see the effect in has on another factor

Listed in the first column of the results table

12

Dependent variable

The factor that you measure or observe in an experiment

This data is added to the results table as the experiment progresses

13

Control variable

A factor that you must keep constant between each repeat of the experiment so the results can be compared

Not recorded in a result table

14

Extraneous variable

A factor that may affect the experiment but that you have not measured or controlled

15

SI units

The International System of Units (SI) states the units that quantities should be measured in

E.g. Distance is measured in metres (m)
Time in seconds (s)
Mass in kilograms (kg)

16

Method

A step-by-step detailed explanation of how to complete an experiment

Should be written in such a way that anyone can follow it and complete the experiment in the same way

The equipment and reagents need to be listed before the method

Fully labelled diagram

17

Tables

First column = independent variable, can be completed before experiment

Other columns contain the dependent variable

Each column heading must be labelled with the variable and its unit of measurement

Entries to the table don't require units as they are recorded in the headings

18

Continuous variables

A measured value that could be any number

E.g. Temperature

19

Discrete variables

Values can only be definite numbers

E.g. Atomic number

20

Categoric variables

A qualitative description

E.g. The colour of a precipitate

21

Independent variable

X axis (horizontal axis)

22

Dependent variable

Y axis (vertical axis)

23

Scatter graph

Both variables must be continuous

24

Line graph

The independent variable can be discrete or categoric

The dependent variable can be continuous or discrete

25

Bar chart

The independent variable can be discrete or categoric

The dependent variable can be continuous or discrete

26

Scatter graphs

Maximise graph paper use so trends are easy to observe

Choose a suitable scale (this may or may not mean starting at the origin)

Independent variable - continuous, on x-axis

Dependent variable - also continuous, on y-axis

27

Lines of best fit

No pattern = don't draw a line of best fit

If a data point doesn't fit the pattern, circle it, ignore the anomalous result

Pattern is a straight line - use a ruler, use a sharp pencil, draw the line, don't just connect the dots - draw the pattern the data shows

Pattern is a curve - draw a smooth curve - hold pencil firmly on the desk and move the paper to get a smooth curve

28

Gradient

Change in y DIVIDED BY change in x

29

Concordant results

Values that are close to each other and therefore represent reliable data

Results that aren't concordant are anomalous

Only concordant results are used to calculate an average

30

Accurate

Results close to the true value