7A Being a Scientist Flashcards
Why must you never enter the laboratory without a member of staff present?
In case there is something dangerous in the lab
What is a hazard?
Something that can harm you
What does minimise mean?
To reduce
What is a symbol?
A letter or picture which represents something
Why are symbols useful?
They can be understood regardless of language
What do you think flammable means?
Catches fire easily
Why do you think one of the symbols is a skull and bones?
It shows it is toxic – it can kill you
What might oxidising mean?
Adding oxygen
What might be the difference between a concentrated and dilute acid?
Dilute acid has more water and is usually less dangerous
What is a hazard?
Something that can cause harm
Define the term risk factor.
How likely it is that a hazard will cause harm
What is an emergency procedure?
What you should do if something goes wrong
What is a risk?
The harm a hazard can cause
Name a hazard associated with mixing chemicals.
Splashing into your eye or onto your skin
Name a risk associated with using acids.
Can burn or irritate the skin or eyes
Describe the safety precautions for using glassware.
Do not use if chipped, place in middle of bench, place test tubes in test tube rack
Describe the emergency procedure if you spill acid on your skin.
Wash immediately, then tell teacher
What is a microscope?
An instrument which allows us to see very small objects, like cells
Name 2 pieces of scientific glassware.
Beakers, conical flasks, test tubes, stirring rod
What piece of equipment should be used if you only need to react a small amount of a chemical?
Test tube or boiling tube
What piece of equipment should be used if a solution needs to be plugged?
Conical flask
What is the function of a Bunsen burner?
To heat chemicals
Why do scientists use scientific diagrams?
To represent equipment needed and how to set it up for an experiment
What should be used to draw a scientific diagram?
Pencil
Why do you need to be able to measure something?
To get results, e.g. for an experiment
What does dm stand for?
Decimeters
How do you convert cm to metres?
÷ 100
What does convert mean?
To change something
Why do we need to convert values?
To make them easier to write – fewer zeros
What does centimetre actually mean?
100th (centi-) of a metre
Name 3 pieces of scientific equipment made from glass.
Beaker, stirring rod, test tube, boiling tube, flask, thermometer
Where should we place glassware when not in use?
Middle of bench
Where could you place a test tube during an experiment?
Test tube rack
What are the hazards associated with using a Bunsen burner?
Chimney will be hot, open flame
Which part of a Bunsen burner will be hot after use?
Chimney
What should you do after using a Bunsen burner?
Allow it to cool
What equipment could you use to measure hydrochloric acid?
Measuring cylinder
What equipment could you use to transport a solid powder?
Spatula
Name a piece of equipment that can be used to measure volume.
Measuring cylinder
Name a piece of equipment that can be used to measure temperature.
Thermometer (digital, glass or infrared)
Name a piece of equipment that can be used to measure force.
Newton meter
What units are temperature measured in?
Degrees Celsius (°C)
What units are volume measured in?
cm3
What units are force measured in?
Newtons
Which specific piece of equipment could you use to measure 35cm3 of a liquid?
(50 ml) measuring cylinder
Which specific piece of equipment could you use to measure the temperature of boiling water?
Digital or glass thermometer
Name two pieces of safety equipment.
Goggles and apron
What is the purpose of filtration?
To remove an insoluble solid from a mixture
How must you fold the filter paper during filtration?
In half and half again
Name a piece of equipment from the text that can be held by a clamp stand.
Boiling tube
What equipment do you use to stir a solid in a liquid?
Stirring rod
Why are the acids we use in science in low concentration?
So they do not cause serious harm
What are forceps used for?
To pick up objects
What should you wear throughout all these experiments to keep yourself safe?
Goggles and an apron
What is a Bunsen Burner used for?
As a source of heat
What is the function of the base?
To keep the Bunsen burner from falling over
What is used to connect the Bunsen Burner to the gas tap to transfer the gas to the chimney?
Rubber hose
What is the purpose of the air hole?
To allow oxygen to mix with the gas
How do you put the Bunsen Burner onto the safety flame?
Close the air hole
Why is it important to use the safety flame when the Bunsen Burner is not in use?
It is more visible so less likely that it will cause harm
What is incomplete combustion?
Combustion in a lack of oxygen
Which type of flame produces more heat?
Blue, roaring flame
When should you turn the gas tap on?
When you have a lit spill above the chimney
What type of flame do you get when you leave the air hole closed?
Orange, safety flame
What equipment is missing from the description on lines 18 and 19?
Gauze, heatproof mat
What safety precautions should you take when using a Bunsen burner?
Wear goggles and apron, stand up, tie hair back
When you have finished with the Bunsen burner how do you turn it off?
Turning off the gas tap
What does water look like when it is boiling?
Bubbles throughout, steam given off
What is accuracy?
A measurement or result that is close to the true value
Why is it important that are results are accurate?
So that we know our experiment has the correct outcome
What is resolution?
The smallest change in the quantity being measured
Which thermometer would give you a more accurate result, glass or digital?
Digital
Explain why.
It has a smaller resolution and is easier to read so will give a reading which is closer to the actual value
What piece of equipment would you use to measure the height of a person?
Metre ruler
What would you use to measure the weight of a shoe?
Newton meter
What would you use to measure volume of water?
Measuring cylinder
What information should be included in an experimental plan?
Variables, equipment, method, and risk assessment
Name some possible control variables.
Starting height, volume and frequency of watering, type of plant, soil
Why are control variables important?
They give us reliable results
Define the term “reliable”
If we repeat the experiment, we will achieve the same results
Why is an equipment list important?
We know what to use, we can complete a risk assessment
Why must a risk assessment be completed?
So we are aware of hazards and what to do if something goes wrong
Why do we draw results tables?
To record the results of an experiment
Where does the independent variable go in a results table?
The first column
Where does the dependent variable go in a results table?
The second column
Why are tests repeated 3 times?
To calculate a mean
Why is a mean result taken?
To spot patterns more easily
Why is it important to add units to a table?
To understand what the numbers mean
How are values arranged in the first column of a table?
In numerical order, usually smallest to largest
Why aren’t control variables shown in the table?
These are kept the same and not recorded
Why do we collect more than one set of data?
To identify anomalies
What is an anomaly?
A result that doesn’t fit the rest of the results
What might cause an anomaly?
Human error, equipment error
What 2 things could you do if you have an anomaly?
Repeat or ignore when calculating mean
What is a trend?
A pattern shown by the results
How can you check your mean calculation is correct?
The mean should be a similar value to the results
What is a solution?
A mixture formed by a solute and a solvent
What is a soluble substance?
One which dissolves
What is an insoluble substance?
One which does not dissolve
What is the solute in salt water?
Salt (the solid)
What is the solvent in salt water?
Water (the liquid)
What happens to particles when they dissolve?
They spread out equally in the solvent
What is a saturated solution?
A solution where no more solute can be dissolved
How can we increase the amount of solute that dissolves in a solvent?
Heating the solvent
Why do we draw a graph of our results?
To observe patterns in the data
Give two examples of graphs.
Line graphs, bar charts, histograms, pie chart
Which axis, vertical or horizontal, is the x-axis?
Horizontal
On which axis should the dependent variable be plotted on?
Y axis
How much of the graph paper should a graph take up?
At least half
What are the two types of lines of best fit?
A straight line or a curve
Why do we draw a line of best fit?
It makes the patterns observable
Give two reasons why we plot data as a graph.
Easier to identify patterns, Easier to identify anomalies.
What is an anomaly?
Something that does not fit with the rest of the data.
What is a relationship?
How two or more variables are related.
Where is a graph’s origin?
At 0 on the x and y axis
What is the x-axis on a graph?
The horizontal line
What does the term directly proportional mean?
The independent and dependent variable increase at the same rate
Which type of relationship is shown by a upward slope?
Positive
Which type of relationship is shown by a downward slope?
Negative
What sort of graph can we find gradient on?
Line graph
Which axis is the x-axis?
Horizontal
What must be drawn accurately to find gradient?
Line of best fit
What do you need to draw on your graph to find gradient?
A triangle
What quantities can you find using gradient?
Speed
What is the unit for speed?
m/s
How can this be determined from a graph?
Change in vertical (distance) ÷ Change in horizontal (time)
If you have a curve of best fit what might you do to determine gradient?
Draw a tangent (a straight line which touches the curve)
