Module 1.1 Practical skills assessed in a written assessment

Question 1

Primary research

Answer 1

New data is collected and conclusions are then drawn

Question 2

Secondary research

Answer 2

Data from other studies is used to draw conclusions

Question 3

Valid results

Answer 3

Are suitable results that can test the aim

Question 4

Hypothesis

Answer 4

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

Question 5

Surveys

Answer 5

A type of primary research

Sets out limits to observe something already happening

Question 6

Meta study

Answer 6

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

Question 7

Quantitative data

Answer 7

Has a numerical value

Requires a measuring instrument to be observed

Question 8

Qualitative data

Answer 8

Descriptions of what is observed

Question 9

Resolution

Answer 9

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

Question 10

Accuracy

Answer 10

How close to the true value a measurement is

Question 11

Independent variable

Answer 11

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

Question 12

Dependent variable

Answer 12

The factor that you measure or observe in an experiment

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

Question 13

Control variable

Answer 13

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

Question 14

Extraneous variable

Answer 14

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

Question 15

SI units

Answer 15

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)

Question 16

Method

Answer 16

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

Question 17

Tables

Answer 17

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

Question 18

Continuous variables

Answer 18

A measured value that could be any number

E.g. Temperature

Question 19

Discrete variables

Answer 19

Values can only be definite numbers

E.g. Atomic number

Question 20

Categoric variables

Answer 20

A qualitative description

E.g. The colour of a precipitate

Question 21

Independent variable

Answer 21

X axis (horizontal axis)

Question 22

Dependent variable

Answer 22

Y axis (vertical axis)

Question 23

Scatter graph

Answer 23

Both variables must be continuous

Question 24

Line graph

Answer 24

The independent variable can be discrete or categoric

The dependent variable can be continuous or discrete

Question 25

Bar chart

Answer 25

The independent variable can be discrete or categoric

The dependent variable can be continuous or discrete

Question 26

Scatter graphs

Answer 26

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

Question 27

Lines of best fit

Answer 27

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

Question 28

Gradient

Answer 28

Change in y DIVIDED BY change in x

Question 29

Concordant results

Answer 29

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

Question 30

Accurate

Answer 30

Results close to the true value

Question 31

Reliable

Answer 31

Results that are similar when they are repeated

Question 32

A false positive

Answer 32

When a positive result is produced but not due to the desired product being formed

Question 33

Systematic error

Answer 33

The same error in every measurement

Due to the limits of the equipment e.g. a piece of measuring equipment not being correctly calibrated

Question 34

Random error

Answer 34

An error that may or may not be present

Different every time

Due to the experience of the scientist e.g. not controlling draughts in a room

Question 35

Margin for error

Answer 35

Shows the range that a value lies within

Question 36

Precision

Answer 36

The degree to which repeated values, collected under the same conditions in an experiment, show the same result

Question 37

Weighing by difference

Answer 37

Mass of container before and after a material is added and the difference between these values is the mass of the material

Question 38

Percentage error

Answer 38

A mathematical way of comparing the experimental value with the actual value

Question 39

Margin for error of a 50 cm^3 measuring cylinder

Answer 39

+ or - 0.1 cm^3

Question 40

Margin for error of a 10 cm^3 measuring cylinder

Answer 40

+ or - 0.01 cm^3

Question 41

Margin for error of a 50 cm^3 pipette

Answer 41

+ or - 0.05 cm^3

Question 42

Percentage error of a value

Answer 42

Actual value - experimental value DIVIDED BY accepted value

TIMES BY 100

Question 43

Percentage error of equipment

Answer 43

Maximum error DIVIDED BY measured value

TIMES BY 100