Science is a way of investigating and improving our understanding of our world and wider universe beyond it. It involves:
generating and testing ideas
gathering evidence by carrying out investigations
communicating and debating the findings with others
Scientific progress comes from logical, systematic work carried out by scientists from all cultures, building on the historical knowledge of past researchers.
Scientists are creative, insightful people who develop ideas built on a foundation of evidence. They are adding to the huge amount of scientific knowledge. An important part of science is that this information is shared between scientists all over the world. Their ideas and the evidence to support them are open to be challenged internationally, and over time can be modified, added to and developed into a scientific theory. Or, if the evidence from other scientists does not support their findings, their theory will be modified and dropped.
Science helps us develop an understanding of our world built on current scientific theories. It teaches us a way of tackling problems to gain further knowledge. A scientific approach involves seeking out and critically examining the evidence for and against an idea. Science is about investigating the world around us. We do this to discover:
why things happen, so we can predict how they will happen in the future
what chemicals things are made of and how they will react
why living things work in the way they do.
Main areas of science:
Biology- the study of living things
Geology- the study of rocks and the Earth
Chemistry-the study of chemicals
Physics-the study of movement and energy
Astronomy-the study of planets and stars
These areas can be further broken down into smaller subject areas. e.g. biology can be split into zoology (study of animals), botany (study of plants) and ecology (study of how living things interact).
Majorly the areas of science are grouped into four sections:
Before you begin any practical work it is important that you think carefully about being smart and staying safe in the laboratory.
So here's an introduction to our rules:
There are two main rules to follow.
Know what you are doing in the laboratory. Read the instructions carefully before you start.
Always think of others and behave sensibly.
Other important rules to remember are:
Do not enter the laboratory unless you are with your teacher.
Never touch equipment in the laboratory unless you are told to use it.
Don't eat in the laboratory.
Always walk - never run.
Wear protective clothing - especially safety glasses.
Never taste chemicals.
Don't use paper to light Bunsen burners, and don't put burning things in the rubbish bin.
keep books, paper, long hair and clothing away from flames.
Always point test tubes away from people.
Check with your teacher on how to dispose of waste liquids and solids. Broken glass should be placed in a special bin.
If you spill something on your clothes wash it immediately with plenty of water. Tell you teacher.
Report all accidents and breakages to your teacher.
After heating equipment, let it cool down before picking it up. This will avoid burns.
Clean all equipment after use and put it back where you got it from. Clean your work bench if there is a spill and after doing experiments.
IF AN ACCIDENT DOES OCCUR, REPORT IT TO YOUR TEACHER.
Eye injuries can be caused by liquids splashing into your eyes during experiments. Always wear your safety glasses. Also never point a test tube towards your face or anyone else's.
Poisoning can be caused by breathing in fumes during an experiment, eating chemicals or by spilling them onto your skin. Do not eat or drink in the lab.
Cuts are caused by broken glass, so make sure any broken glass goes into the labelled bin.
Burns can be caused by touching hot equipment, or by spilling hot liquid when someone bumps you. Treat burns with cold running water. Serious burns can occur with a Bunsen burner. If this happens, tell your teacher at once.
Fires are always possible when using burners. It is essential to tie back long hair whenever you are using a burner.
Damage to clothing and skin can occur when chemicals especially corrosive liquids such as acids and alkalis, are spilt. If there is a spill, wash the area immediately with lots of water and send someone to tell the teacher. In the most serious cases you may need to use the safety shower.
Damage to the laboratory can occur when sinks become blocked with paper or solids, which can cause flooding if the taps are left running. The benches can also be scorched during heating. They can also be damaged by chemical spills, so wipe these up immediately.
Laboratory equipment
In the science lab you will find lots of different equipment. Before you can start doing experiments, you need to know what equipment is called and what it can be used for. You also need to know how to draw them as part of a scientific diagram.
Containers:
Beaker
Conical flask
Round bottomed flask
Test tube
Measuring cylinder - for measuring volumes of liquids
Evaporating basin - for heating liquids strongly
Watch glass - for heating solutions and holding small amounts of solids
Crucible, lid and pipeclay triangle - apparatus for heating solids to high temperatures. The pipeclay triangle is placed on top of a tripod.
For each piece of equipment listed- write the name, draw a scientific diagram and write what they are used for.
Holding things:
Test tube rack - the rack is used for holding test tubes and the pegs are used for drying test tubes
Test tube holders
Metal tongs - for holding small objects, especially when heating
Metal stand
Clamp
Bosshead - for attaching clamp to stand
Stand and clamp - for supporting apparatus
For each piece of equipment listed- write the name, draw a scientific diagram and write what they are used for.
Heating apparatus:
Bunsen burner
Gauze mat - to spread the heat evenly
Tripod
Heatproof mat - to protect the bench
For each piece of equipment listed- write the name, draw a scientific diagram and write what they are used for.
Other useful items:
Dropper - for dispensing liquids one drop at a time
Dropping bottle - for dispensing liquids
Glass stirring rod
Spatula - for picking up small amounts of solids
Funnel - for filtering
Test tube brush - for cleaning test tubes
For each piece of equipment listed- write the name, draw a scientific diagram and write what they are used for.
Put on safety glasses
Put the Bunsen burner on a heating mat
Connect the gas tube to the gas tap
Close the air hole by turning the collar
Strike a match and hold it over the top of the barrel
Turn on the gas at the gas tap
When the gas lights, open the air hole until a blue or clear flame forms
If the Bunsen burner goes out, turn off the gas and start again
When using a Bunsen burner, set it to a blue or clear flame. If you wish to leave your Bunsen burner going while you do some work or collect more equipment, close the air hole so that you have the yellow or safety flame.
To heat liquids in a test tube, you use a test tube holder. The test tube needs to be held near to the top, and tilted on an angle so that only the bottom of the test tube is in the Bunsen burner flame.
The top of the test tube must always be pointed away from other students when heating, and you must stop if the liquid you are heating starts to boil.
Mass- is a measure of the amount of something
measured in grams or kilograms
Length- is a measure of size
measured in millimetres, centimetres and kilometres
Time- is measure of how long you leave an experiment
measured in seconds, minutes, days, weeks or years
Temperature- is a measure of how hot something is
measure in degrees celsius.
Freezing point of water is 0℃
Boiling point of water is 100℃
Volume- is a measure of the amount of space an object occupies
measured in millilitres or litres
Parallax error occurs when the measurement of an object's length is more or less than the true length because of your eye being positioned at an angle to the measurement markings.
What is Meniscus?
The meniscus of a liquid is the upward or downward curve seen at the top of a liquid in a container. The nature of curve whether upward (convex) or downward (concave) depends on the surface tension the liquid and its adhesion capacity to the wall of the container.
Concave Meniscus (See diagram A)
A concave meniscus occurs when the molecules of liquid are strongly attracted to the container wall rather than to each other. In that case, liquid appears to ‘stick’ from the edges forming a concave shape.
Convex Meniscus (See diagram B)
A convex meniscus appears when molecules of liquid are strongly attracted to each other rather than to the wall of container. Most liquids, including water, show a concave meniscus but a great example of a convex meniscus is liquid mercury in a glass container. It is to be noted that in some cases, the meniscus appears in a straight line instead of any curvature at all. For example, water in some plastic cylinders. No meniscus makes measuring very easy.
How to read a meniscus correctly
You must get at eye-level with the meniscus to obtain an accurate reading. Pick up the glassware to bring it up to eye level or bend down to take a measurement.