ChemSci Tutor

09/10/2026

Element of the Week: 1 Mercury Hg

Mercury is unique being the only metallic element that is a liquid at room temperature (see Photograph 1). It has a high density such that a known volume of mercury in a container weighs 13.5 times more than the same volume of water. It is found next to gold in the Periodic Table and was used by alchemists in ancient times who found it when extracting gold from its ores. It is named after the planet mercury. Mercury forms amalagams with many other metals and these were often used in dental fillings because they are hard wearing. It was also used in thermometers and barometers (see photograph 2). Most of these uses have now been discontinued due to mercury's toxicity.

Written by Helen Hart ChemSci Tutor Please like or follow this page for more information and stories.

Photograph 1 by Tavo Roman Photograph 2 by Helen Hart

07/10/2026

Chemistry Laboratory Equipment Week 3: The Burette is used in titrations at GCSE and A level. This is how to use a burette:
1. Make sure that the tap is closed and moves freely.
2. Place a filter funnel in the top and hold the burette so the top is at eye level. Pour the acid solution into the burette so its near the top. It does not need to be lined up at this stage.
3. Remove the funnel and clamp the burette onto the stand, making sure that it is vertical.
4. Then let some liquid out slowly using the tap into an empty container, so that the volume reading is clear. It does not have to be zero. Record the initial volume reading.
5. Place the conical flask containing the alkali under the burette and add a few drops of indicator. Add the acid from the burette and swirl the indicator solution to see if it changes colour.
6. When you are close to the end point, the indicator may change colour for a short time, but go back to the original colour on mixing. At this stage, add solution from the burette drop-wise until a permanent colour change is seen. Record this volume reading and subtract the initial volume reading to give the volume added (the titre).
7. Repeat until you have 3 results that are close to each other, 0.1 ml difference is possible, and take an average.

Written by Dr Helen Hart ChemSci Tutor Please like or follow this page and share with your friends.

Photograph by ArtyBeeKids

01/10/2026

Your Questions Answered: "Applying for Secondary School Y7: Science" Open evenings are now being held for secondary school applications for September 2027 entry. Science is a core subject and all children study Science from Y7 to Y11. I would recommend visiting a Science laboratory as part of your visit. Some schools encourage children to try out hands-on activities or have practical demonstrations as part of the visit. However, this may not be a reliable way of showing how the school teaches Science every day. Although the GCSE exam structure could change, look at the following:
- which pupils study Combined Science (2 GCSEs) and 3 separate Sciences?
- are pupils set according to ability in both separate and Combined Science?
- are options for lower-ability pupils available e.g. BTEC level 2 Science?
- are there any Science after-school or lunch-time clubs?
- are there opportunities for educational visits or competitions such as the Chemistry Olympiad?
- if the school has a sixth form, check what is needed to progress to A level and the balance between male and female pupils.
- other Science options such as Astronomy may be available at GCSE. This is rare in the state sector, but there may be clubs for this subject.

Note: sixth form entry will be covered in a later post.

Written by Dr Helen Hart ChemSci Tutor Please like or follow this page for more information and stories.

Image by Freepiks

26/09/2026

Chemistry Laboratory Equipment Week 2: The Pipette is used to transfer a known, accurate volume of liquid or solution into a beaker or conical flask. There are 2 types of glass pipette. The first type (photograph 1) has a printed scale on the side and allows you to transfer a variety of different volumes. You need to make sure that the meniscus is lined up with the desired volume. The second type (photograph 2) has a single line on the stem and you need to fill the pipette up to that line to have a volume of 25 ml.
Pipettes are used in experiments that require precise volumes e.g. titrations, rate of reaction practicals and calorimetry.
For safety a rubber bulb is used to help fill pipettes, se photograph 3. Putting pipettes in your mouth is not recommended.

Written by Dr Helen Hart ChemSci Tutor Please like or follow this page for more information and stories.

Photograph 1 by Nathan Rimoux on Unsplash Photograph 2 public domain
Photograph 3 Cristian Wait on Pixabay

14/09/2026

Chemistry Lab Equipment Week 1: The Conical Flask (Erlenmeyer flask or titration flask) is a type of laboratory flask with a flat bottom, a conical body, and a cylindrical neck. It was invented by the German chemist Emil Erlenmeyer (1825–1909) in 1860. The slanted sides and narrow neck of this flask allow the contents to be mixed by swirling, without risk of spillage, making them suitable for titrations. Conical flasks are also suitable for boiling liquids because hot vapour condenses on the upper section reducing solvent loss. The flask's narrow neck can also support filter funnels and are part of the apparatus needed in the separation of salts practical. The volume markings on Conical flasks are not suitable for accurate volumetric measurements.
This series is inspired by helping my students revise for GCSE and A level Chemistry practicals.
Written by Dr Helen Hart ChemSci Tutor Please like or follow this page for more information and stories.
Can you guess what the solution in Photo 2 might be? Please comment below.

Photograph 1 by Jenny Hart Jen's Photographic Art Photograph 2 from Magnific.

09/09/2026

A big welcome to all students starting sessions with ChemSci Tutor for the 2026-7 academic year over the next couple of weeks.
Lessons for returning students in Y11 and Y13 start this week.
Lessons for new students will starting next week.

Look forward to meeting you all.

Photo by Maria Lin Kim on Unsplash

13/08/2026

Best Wishes to my A level Chemistry students receiving their results today.

08/08/2026

On Weds 12th August from 6.15 to 8 pm BST there is going to be a total solar eclipse visible in Northern Spain. In the UK and the rest of Europe, there will be a partial eclipse with up to 95% of the sun covered depending on your location. The highest coverage will be in Cornwall.
It is also possible to view the eclipse by livestream from the Royal Observatory Greenwich using the following link https://buff.ly/9RliwH8

What is an eclipse? A total eclipse occurs when the moon passes directly over the Sun and causes a short period of darkness. The safest way to view an eclipse is via a pinhole in a piece of paper and projecting onto paper or a screen. Do NOT look directly at the sun.
Written by Dr Helen Hart ChemSci Tutor Please like or follow this page for more information and stories.

Join the Royal Observatory Greenwich live online to watch the 90% partial solar eclipse visible from the UK

31/07/2026

Summer Science Weather 2: How to Make a wind-sock out of plastic.
Wind socks give an idea of the wind direction and speed. The open end points toward where the wind comes from, and the tail points to where the wind is going.
You will need a clean, plastic bottle, a plastic bag and some string.
1. take the plastic bottle and cut a plastic ring across the main part of the bottle. You may need an adult to help.
2. Then take a hole puncher and form 2 holes on opposite sides of the ring.
3. Thread a piece of string through the holes to make a handle. Cut a piece of string that is 3 to 4 times the length of your ring. Thread it through both holes, then tie both ends together to make a handle.
4. Take a plastic carrier bag and draw straight lines about 2.5 cm wide. Cut the strips carefully and tie them round the ring from the bottle. You can use different colours as desired. Tissue paper can also be used, but this will not be waterproof.
5. Hang up your windsock on a hook in your garden and have fun using it!

This idea was taken from WikiHow.

Adapted by Dr Helen Hart ChemSci Tutor Please follow this page for more holiday ideas and stories.

24/07/2026

Summer Science Weather: The weather has been in the news over the past few days with record temperatures being reached in the UK. Here are some ideas for you to monitor the weather yourself.
Temperature can be measured using a thermometer. Choose one designed for the house or garden such as the one shown. Temperature readings can be taken in different ways e.g. once an hour to work out the hottest and coolest time of day or measure every day at the same time over several days. Results can be shown in a graph or chart.
Rainfall can be measured using any plastic container placed somewhere where it won't be knocked over. As long as you use the same container each time, the size does not matter. You can either measure the depth of the water using a ruler or pour the water collected into a measuring cylinder to work out the volume collected. Alternatively, the density of water is about 1 g per cubic centimetre. Which means that the weight in grams gives you a value for the volume as well.

Written by Dr Helen Hart ChemSci Tutor Please like or follow this page for more information and stories.

Photograph 1 public domain Photograph 2 public domain