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KEGS Chemistry
Великобритания
Добавлен 22 окт 2015
Chemistry videos produced at King Edward VI Grammar School, Chelmsford, Essex, UK
Advanced Level videos relate to UK A Level Chemistry Specifications:
OCR Chemistry A (AS/A2 - from 2008) (H434)
OCR Chemistry A (linear - from 2015) (H432)
General Level videos relate to UK GCSE Chemistry Specification:
AQA GCSE Chemistry 9-1 (8462)
Advanced Level videos relate to UK A Level Chemistry Specifications:
OCR Chemistry A (AS/A2 - from 2008) (H434)
OCR Chemistry A (linear - from 2015) (H432)
General Level videos relate to UK GCSE Chemistry Specification:
AQA GCSE Chemistry 9-1 (8462)
KAC 31.3 - Single Step Redox Titration Calculations
How can you carry out unstructured calculations based on redox titrations such as potassium manganate(VII)?
00:00 - Introduction
02:02 - Example: Finding an unknown concentration
05:38 - Example: Finding the formula of a hydrated salt
00:00 - Introduction
02:02 - Example: Finding an unknown concentration
05:38 - Example: Finding the formula of a hydrated salt
Просмотров: 518
Видео
Paper Chromatography: Solvent Effect
Просмотров 8 тыс.3 года назад
How does the solvent used affect separation of mixtures by paper chromatography? In this video we test inks from two identical pens (washable purple felt tip and black 'permanent' marker) in water and ethanol and see how the chromatograms look at the end.
Experiment: Temperature Changes in a Displacement Reaction
Просмотров 2,3 тыс.3 года назад
How can you measure the temperature change in a rection between zinc and copper sulfate solution? This video shows how this experiment can be carried out quickly in a reasonably accurate fashion on a small scale to minimise waste. The experiment in this format can be used for Required Practical 4 as part of AQA GCSE Chemistry 9-1 (8462) Please not the hazards associated with the chemicals and d...
KAC30.6 - Redox II: Extracting Half-equations from a Redox Equation
Просмотров 3983 года назад
How can you find the oxidation and reduction half-equations hen you know the full equation? Two methods are exemplified here: 00:00 - Subtraction - when one half-equation is known 03:30 - Building up from key species - to suggest both half-equations from the full equation.
Temperature Changes During and After a Reaction
Просмотров 903 года назад
What happens to the temperature of a reaction it has stopped? In this demonstration water is heated for about 3 min and then the gas is turned off. Let's see what happens...
Zinc-Copper Electrochemical Cell Demonstration
Просмотров 2,6 тыс.3 года назад
What do you need to make an electrochemical cell? This video demonstrates that a voltage is produced between pieces of zinc and copper when they are both placed in solutions containing ions. The zinc and copper half-cells are connected by a salt bridge, which allows ions to flow between them. The video finishes with a discussion of the sign of the voltage produced, which depends on the choice o...
Standard Hydrogen Electrode Demonstration
Просмотров 26 тыс.3 года назад
How can you measure standard electrode potentials? This video is deisgned to be shown in place of a classroom demonstration of the working of the standard hydrogen electrode and its use in measuring standard electrode potentials. 00:00 - Creating the standard hydrogen electrode 01:10 - Measuring Standard Electrode potentials #1: Zn|Zn2 (focus: connecting the voltmeter) 02:16 - Measuring Standar...
KAC25.10a - Preparing Reaction Mixtures for Initial Rates Experiments
Просмотров 453 года назад
How can you prepare mixtures with specific concentrations of two or more reagents? Considering a situation where you have concentrated stock solutions of both reagents available (far easier than weighing different masses out each time). The video discusses: 00:00 - Basic principles for designing such experiments 03:27 - Finding concentrations when two reagents are mixed 06:35 - Finding volumes ...
Effect of Charged Rod on Liquids
Просмотров 1,7 тыс.3 года назад
What happens when you bring a charged rod near to a jet of water? Does it matter what charged the rod has? Do other liquids behave the same way? These questions are answered in this video. An opaque white nylon rod is used which picks up a positive charge when rubbed, and a transparent acrylic rod picks up a negative charge.
KAC 5.1 - Titrations: Understanding the Principle
Просмотров 1183 года назад
Why do you carry out a titration? How does it work? This video goes over the main stages in a titration experiment (without practical details) and then explores what is going on at the microscopic level during a titration. Crucially, at the end-point we infer that substances have reacted according to the mole ratio in the equation.
KAC5.2 - Titration Calcaulations
Просмотров 1123 года назад
How can you use the results of titrations to calculate unknown concentrations, volumes, etc.?
Gas Collection Over Water
Просмотров 19 тыс.3 года назад
How can you successfully collect a gas by water displacement? 00:00 - The apparatus in action 00:33 - Choosing your apparatus 02:13 - Setting up the apparatus This method is only suitable for collecting gases which are not soluble in water!
Reaction of Iodine and Sodium Hydroxide - a Disproportionation reaction
Просмотров 7 тыс.3 года назад
Reaction of Iodine and Sodium Hydroxide - a Disproportionation reaction
Measuring Conductivity of Solids and Aqueous Solutions
Просмотров 8 тыс.3 года назад
Measuring conductivity of solids and aqueous solutions using a digital multimeter, which shows the current passing through the samples. 00:00 - Sodium Chloride 00:18 - Potassium Chloride 00:31 - Sucrose
Following pH Changes During Neutralisation
Просмотров 2413 года назад
How does pH change when different types of acid and base are added to each other? 00:00 - Here the pH is followed during neutralisation using a pH probe and datalogger for the following combinations of acid and base: 00:46 - Strong acid & strong base (HCl & NaOH) 02:03 - Weak acid & strong base (CH3COOH & NaOH) 03:17- Strong acid & weak base (HCl & NH3) 04:31 - Weak acid & weak base (CH3COOH & ...
Acid and Metal Oxide Reaction: Nitric Acid and Copper(II) Oxide
Просмотров 5 тыс.3 года назад
Acid and Metal Oxide Reaction: Nitric Acid and Copper(II) Oxide
Acid and Metal Hydroxide Reaction: Hydrochloric Acid and Sodium Hydroxide
Просмотров 2,8 тыс.3 года назад
Acid and Metal Hydroxide Reaction: Hydrochloric Acid and Sodium Hydroxide
Buffer Demonstration 2: Partially Neutralised Weak Acid
Просмотров 823 года назад
Buffer Demonstration 2: Partially Neutralised Weak Acid
Acid and Metal Carbonate Reaction: Sulfuric Acid and Magnesium Carbonate Powder
Просмотров 4,2 тыс.3 года назад
Acid and Metal Carbonate Reaction: Sulfuric Acid and Magnesium Carbonate Powder
Acid and Metal Reaction: Citric Acid and Magnesium Ribbon
Просмотров 3,5 тыс.3 года назад
Acid and Metal Reaction: Citric Acid and Magnesium Ribbon
Buffer Demonstration 1: Weak Acid and its Salt
Просмотров 1743 года назад
Buffer Demonstration 1: Weak Acid and its Salt
Measuring Conductivity of Dilute Acids in Water
Просмотров 7793 года назад
Measuring Conductivity of Dilute Acids in Water
Comparing Reactions of Hydrochloric Acid and Ethanoic Acid with Sodium Carbonate and Magnesium
Просмотров 9 тыс.3 года назад
Comparing Reactions of Hydrochloric Acid and Ethanoic Acid with Sodium Carbonate and Magnesium
KAC31.6 - Titrations II (Redox): Finding Mole Ratio (Stoichiometry) from Multiple Equations
Просмотров 7834 года назад
KAC31.6 - Titrations II (Redox): Finding Mole Ratio (Stoichiometry) from Multiple Equations
KAC31.4 - Titrations II (Redox): Iodine/Thiosulfate Titrations
Просмотров 3,3 тыс.4 года назад
KAC31.4 - Titrations II (Redox): Iodine/Thiosulfate Titrations
KAC31.5 - Titrations II (Redox): Multi-step Redox Titration Calculations (Iodine/Thiosulfate)
Просмотров 8834 года назад
KAC31.5 - Titrations II (Redox): Multi-step Redox Titration Calculations (Iodine/Thiosulfate)
Iodine / Thiosulfate Redox Titration Demonstration
Просмотров 120 тыс.4 года назад
Iodine / Thiosulfate Redox Titration Demonstration
Until now, I have only heard about the hydrogen electrode, and now I see it in practice for the first time. Thank you for this brilliant video 😊👏🥇
Awesome
very clear. Love this.
Thanks man ❤
Why not have the intermediate as 2NO at 11:47 does that work for an answer?
bro why did we connect SHE always to -ve and the other to positive?@KEGS Chemistry
Thanks so much sir
Can you please suggest where can I get these apparatus ?
From Egypt Thanks❤
This was vary useful thanks for sharing
What are your probes made of? I tried this with copper wire and it seemed to cause a chemical reaction!
looks like carbon/graphite
Does anybody know when I can buy the glassware to make a SHE? I am a lab technician in a school.
رائع وواضح كأن يحتاج ترجمة حتى يسهل على الطلاب فهمه.
Thank you. I learnt something especially changing the maximum from being to but choosing the minimum to be -20 and flipping the axis. Thank you. I subscribed.
what is there in conical flask in 2nd case
Good explanation
What order of reaction is this sir?
It's zeroth order as the concentration of iodine doesn't affect the rate of the reaction
thank you for this helpful video
Wow, this makes perfect sense. Thank you for finally answering this (apparently) obscure question!
❤thanks dude for this
This is so interesting 😮
THANK YOU SO MUCH FOR HELPING ME THIS FOR AP CHEM OML
Thanks a milliion
thankyou so much this was very helpful xx
Thank you so much sir for this video. I've been struggling with mole ratios and this video helped me.
lovely bro
lovely ♥️
Great video!!
Thanks. Tic marks on the secondary axis?
Coggins
Coggins
Is the ink water soluble?
Hey, is there anyway you could privide sources?
nice im going to prepare some now!
This doesn’t make any sense how do you just guess it
A truly gorgeous video of the utmost quality
Nice one Pankil, ur commet got 2 likes already
Thanks a lot!
What is the voltage requirement to kick in electrolysis?
The lower the v the slower it works but it doesn't matter much
Legend lad
I have a question. Please why is hydrogen gas needed to flow into the set up?
Because his potential diff 0
how exactly do you identify whether a step is slow or fast
not sure if you still need to know, but it will tell you in the question
dude i love how ur so happy with the graph. Great video !
Amazing
Bro! You Are Awesome Nothing is Better Than Practical Knowledge👍🤩 I am Truly Grateful To You
Abbey awaj nikal
❤️
But the starch is an indicator, you were supposed to add it to the iodine before titrating
As he points out at minute 1:14, the starch is added close to the end-point to avoid inaccurate results because of strong bindings to the iodine
How to indicate the endpoint when the potassium iodide is in the burette during titration?
It's never done this way as you want excess iodide in order to generate a quantity of iodine that is directly proportional to the number of moles of your analyte. If you look at this video it explains more: ruclips.net/video/4YYmj_OtOV4/видео.html
Great tutorial! Thank you 🙏🏻
Is it possible to perform this experiment by filling burette with iodine and conical flask with sodium thiosulfate?
I've never seen it done this way! It would make the colour change very hard to detect as iodine would bind to starch present and make it go black immediately after addition. It would then fade and come back when you added more. Thiosulfate in the burette is much better!