Diffusion – video
This video is a great way to see the diffusion of particles in action:
This video is a great way to see the diffusion of particles in action:
Watch Daniel Radcliffe sing the names of all the elements – it’s just a shame there are now more elements than were written into Tom Lehrer’s famous song…..
There are several things in this video which are “beyond the exam spec” but there are loads of interesting bits…..
This video explains the basics of atomic structure, telling you what is inside an atom:
This is a good interactive demonstration showing how subatomic particles make up the atoms in the Periodic Table.
This excellent video from Tyler de Witt walks you through what isotopes are, and how the relative abundance of those isotopes can be used to calculate the relative atomic mass of an element.
This excellent Tyler de Witt video is an introduction to balancing equations:
And here’s another of the lovely Tyler’s videos with some practice questions and answers on equation balancing:
This is useful to help you to practice how to balance equations:
Here’s an excellent Tyler de Witt video explaining how to calculate the relative formula mass of compounds with:
This video shows how to perform calculations involving mass (in grams), amount (in moles) and relative atomic mass:
This video steps through a very useful method used to calculate reacting masses.
In this video, the lovely Tyler de Witt explains Empirical Formulae and Molecular formulae.
(Please excuse the horrid error right at the start where the video shows a diagram of prop-2-ene, but it is labelled ‘ethene’ by mistake.)
This second video then explains how, if given an empirical formula and a molecular mass, you can calculate the molecular formula:
Here is a video to help you with concentration calculations. In Chemistry, concentration is know as molarity (i.e. the amount per volume).
Note that in the video, the lovely Tyler de Witt uses the unit “liter” for volume, but the correct international unit (as used by UK exam boards) is decimeters cubed (dm3) which is the same thing as Tyler’s “liter”.
and a follow up video with some more examples:
Knowing the answer to “What’s an ion?” is absolutely key to Chemistry.
If you aren’t sure what an ion is, or why the idea of ions is crucial to Chemistry, then you should watch this video:
This should give you a ruff idea of what the difference is between ionic and covalent bonding.
In an electrically neutral ATOM, the number of electrons equals the number of protons.
However, an ION is an atom (or group of atoms) which has either gained or lost some electrons, so for an ION the number of electrons does not equal the number of protons.
This excellent Tyler de Witt video explains this clearly:
This excellent video from the lovely Tyler de Witt explains how to write the formula of an ionic compound:
This video shows how to work out the formula of a compound which contains polyatomic ions:
These videos are a really good introduction to ionic bonding:
These videos are a good introduction to covalent bonding:
This excellent Tyler de Witt video addresses a common mistake around diatomic elements (H2, N2, O2, F2, Cl2, Br2, I2).
For example, if chlorine is in its elemental form (i.e. not bonded in a compound) the formula is Cl2, but when chlorine is bonded to sodium the formula of sodium chloride is NaCl.
This video explains the structure of alloys, including different forms of steel.
Note that a slight improvement could be made in the explanation: the structure of metals should be described as “layers of metal IONS in a sea of delocalised electrons”.
Although quite long, this Tyler de Witt video is a good summary of Electrolysis.
The awesome Professor Sir Martyn Poliakoff shows us the reaction of some alkali metals and water.
Here is a great video on Fluorine, which is the most reactive halogen (group 7):
The reactions of various halogens with iron wool is a great way to see how reactive one halogen is compared to another:
Special thanks to Charlie R for suggesting I add a video on halogen displacement.
This video shows the reaction with oxygen of various elements:
The thermite reaction is used to repair railways: the reaction between aluminium and iron oxide is highly exothermic and produces molten iron.
It should be properly controlled if demonstrated in the lab: watch this video and see how many mistakes in basic lab safety made by this teacher.
This video shows the galvanising of pieces of steel to protect them from rusting:
Here are a couple of videos explaining how to perform titration calculations:
This video introduces reaction profiles which show how energy levels change during exothermic and endothermic reactions, and how this relates to the activation energy of a reaction.
Here are a couple of videos explaining how to do bond energy calculations:
Here is a video introducing reversible reactions:
This video explains how the position of equilibrium in a reversible reaction is affected by changes to temperature.
This video explains how the position of equilibrium in a reversible reaction is affected by changes to pressure.
This video shows the addition reaction between bromine and an alkene.
The observation from the reaction is the colour change from orange to colourless.
This video does not quite use the right language for the various fractions as appropriate to the Edexcel iGCSE, but it is nevertheless a good description of the process. Make sure you use the notes on tutorMyself.com to get the exact language you will need for your exam.
And another somewhat older video showing the industrial process of fractional distillation:
This video introduces the process of cracking, which is used to split a long-chained alkane into shorter-chained alkanes and alkenes.
It also tells you about the test used to distinguish between an alkane and an alkene (addition of bromine water).
And this somewhat older video talks more about the industrial process of cracking:
This video is a good introduction to alkanes and crude oil:
This video introduces alcohols:
This video introduces carboxylic acids:
This video introduces addition polymers:
This video introduces the idea of condensation polymers: