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Clip description Keywords
Acids and Alkalis
Acids and Alkalis

A laboratory demonstration is used to explain how increasing carbon dioxide levels in the atmosphere are causing the pH of the oceans to change.

 
Bacterial growth and pH
Bacterial growth and pH

Duration: 02:23

The use of the pH scale in food chemistry is discussed. The pH of food stuffs is measured to show how bacteria are killed when the acidity is increased. subtitled

 
Bodies dissolved in acid
Bodies dissolved in acid

Duration: 01:01

A news report about a member of a Mexican drug cartel who has told police he used chemicals to dissolve the bodies of hundreds of murder victims.

 
Burning diamonds
Burning diamonds

Duration: 01:36

Jim Al-Khalili recreates Smithson Tennant's famous experiment by burning a diamond to prove it is made from carbon.

 
Burning Steel
Burning Steel

Duration: 03:06

Dr Yan demonstrates if metal gets heavier when you burn it using iron wool.

 
Catalytic formation of nitrogen dioxide in the Ostwald Process
Catalytic formation of nitrogen dioxide in the Ostwald Process

Duration: 00:59

A description of the Ostwald Process of creating nitrogen dioxide by combining ammonia with oxygen.

 
Chemical reactions during cooking
Chemical reactions during cooking

Duration: 01:21

How a chemical reaction takes place during cooking to improve the taste of food. Introduces the terms 'reactants' and 'products'. subtitled

 
Collision theory and rates of reaction
Collision theory and rates of reaction

Duration: 03:25

Collisions of atoms are described as causing reactions. The four ways to speed up rates of reactions are given.

 
Combustion and changes in mass
Combustion and changes in mass

Duration: 02:11

Will the mass of iron wool change when it is burned and if so will it increase or decrease? subtitled

 
Combustion of carbon
Combustion of carbon

Duration: 01:12

Carbon burns in oxygen to form carbon dioxide.

 
Combustion of natural gas
Combustion of natural gas

Duration: 02:19

The burning of methane as a chemical reaction.

 
Conservation of mass in chemical reactions
Conservation of mass in chemical reactions

Duration: 02:51

An introduction to the concept of conservation of mass in chemical reaction using two examples.

 
Elements and compounds
Elements and compounds

Duration: 02:03

An introduction to the difference between elements and compounds, using those present in air as an example.

 
Endothermic / exothermic
Endothermic / exothermic

A demonstration of an endothermic reaction and an exothermic reaction, together with an explanation of the terms.

 
Exothermic chemical reaction
Exothermic chemical reaction

Duration: 02:25

A demonstration of the process that occurs inside reusable hand warmers.

 
Extreme weather causes shortage of rock salt
Extreme weather causes shortage of rock salt

Duration: 01:35

A news report about the shortage of rock salt in the UK caused by the icy weather in February 2009. Some roads in Staffordshire may be forced to close as the council reduces gritting services to preserve salt supplies.

 
Factors affecting the rate of reaction
Factors affecting the rate of reaction

Duration: 01:15

A demonstration of how particle size and concentration can alter the rate of a chemical reaction.

 
Food as an indicator of pH
Food as an indicator of pH

Duration: 00:40

The use of food juices as indicators of acidity and alkalinity is demonstrated. subtitled

 
Formation of ammonia in the Haber Process
Formation of ammonia in the Haber Process

Duration: 01:24

The formation of ammonia by sparking a mixture of nitrogen and hydrogen. This is known as the Haber Process.

 
Formation of iron oxide
Formation of iron oxide

Duration: 00:27

In this cartoon oxygen and iron atoms combine to form a new substance - iron oxide. subtitled

 
Mixtures and compounds
Mixtures and compounds

Duration: 02:26

An explanation of the difference between mixtures and compounds, in which reactants and products are explained.

 
Molecules and compounds
Molecules and compounds

Duration: 02:10

A brief introduction to molecules and compounds, explaining the differences between them and giving examples.

 
Neutralisation - acids and alkalis
Neutralisation - acids and alkalis

Duration: 00:33

How an acid and an alkali can neutralise each other to give a neutral solution with a pH of 7. subtitled

 
Neutralisation - the rebreather
Neutralisation - the rebreather

Duration: 03:16

An investigation into how knowledge of a neutralisation reaction is put to use in diving equipment - looking at a 'rebreather' and how soda lime neutralises exhaled carbon dioxide.

 
Neutralising stomach acid
Neutralising stomach acid

Duration: 00:59

How bicarbonate of soda is used to ease indigestion or neutralise an acid stomach. A reaction takes place to produce harmless salt and neutral water. subtitled

 
Production of dyes from chemical reactions
Production of dyes from chemical reactions

Duration: 03:09

Chemical reactions are used to produce different colours of dye to change the colour of a white football kit. subtitled

 
Rates of Reactions
Rates of Reactions

Laboratory demonstrations of the effect of concentration, surface area, temperature and catalysts on reaction rate.

 
Reactants and products
Reactants and products

Duration: 01:19

An introduction to reactants and products in a chemical reaction. Baking a cake is used as an analogy to describe the differences between mixing and chemically combining substances.

 
Red cabbage indicator
Red cabbage indicator

Duration: 02:23

A demonstration of how to make an acid-alkali indicator from red cabbage.

 
Red cabbage indicator test
Red cabbage indicator test

Duration: 01:37

The presenter uses his red cabbage indicator to test household acids and alkalis.

 
Rocket Test
Rocket Test

Duration: 01:07

Presenter Jem builds a hybrid rocket and tests it in a lab.

 
Taste - raw vs cooked onions
Taste - raw vs cooked onions

Duration: 00:37

Children ask why a raw onion tastes so different from a cooked onion.

 
The chemistry of cooking - raw vs cooked onions
The chemistry of cooking - raw vs cooked onions

Duration: 00:27

A cooked onion is chemically different to a raw onion and has a different taste, look, and smell. subtitled

 
Toffee-powered rocket-bike
Toffee-powered rocket-bike

Duration: 04:31

Presenter Jem's toffee powered hybrid rocket was ingenious but dangerous. See how it was built and why toffee is a better fuel than pork pies.

 
Universal indicator - acid, alkali or neutral?
Universal indicator - acid, alkali or neutral?

Duration: 03:09

Demonstrates the use of universal indicator to test for acids and alkalis and introduces the idea that chemicals can be acidic, alkaline or neutral. subtitled

 
Why is fire hot?
Why is fire hot?

Duration: 4:04

Presenter Greg Foot demonstrates how heat, a fuel and oxygen are required to produce fire. He shows how understanding the science of combustion and how water absorbs heat can be used to prevent fire from injuring the human body.

 

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