Question | Answer |
What are all substances made up of? | Atoms. |
How many types of atom does an element contain? | One. |
How can different atoms bond together? | By giving, taking, or sharing electrons to form compunds. |
What is limestone mainly made of? | Calcium Carbonate (CaCO3) |
What is limestone used for? | Building. |
What happens when limestone is heated? | Thermally decomposes. |
What products are produced when limestone thermally decomposes? | Quicklime + Carbon dioxide (Cao + CO2) |
What happens to some carbonates when we heat them? | They thermally decompose. |
What makes a balanced equation? | Equal numbers of each atom on each side of a chemical equation. |
What is 'The Conservation of Mass'? | Mass of reactants = Mass of products |
What is produced when water is added to quicklime? | Slaked Lime Ca(OH)3 |
How do you create lime mortar? | Mixing Slaked lime with sand and adding water. |
How is cement made? | Heating limestone and clay in a kiln. |
How is concrete made? | Mixing crushed rocks, cement and sand with water. |
How is glass made? | Heating powdered limestone, sand and sodium carbonate very strongly. |
How many elemets does the Earths crust contain? | Many. |
What is a metal ore? | Something that contains enough metal to make it economically worth extracting the metal. |
Are all metals found combined with other elements? | No, unreactive elements such as gold are found pure in their natural state. |
Why is the reactivity series useful in extracting metals? | It helps decide the best way to extract a metal from its ore. |
Can a metal more reactive than carbon be extracted by carbon? | No. |
How do we extract iron from iron ore? | By reducing it with carbon in a blast furnace. |
What are the raw materials used to make iron? | Iron ore, coke, limestone. |
Where is molten iron in the blast furnace? | At the bottom, |
Why isnt pure iron very useful? | Too soft. |
How can the properties of iron be changed? | By adding controlled amounts of other elements are added to iron to make alloys of steel with different properties. |
Name some metals alloyed with others to mak them more useful. | Copper, Gold, Aluminium. |
How can we control the properties of alloys? | By adding different amounts of different elements. |
What are smart alloys? | When deformed, they return to original shape. |
How can smart alloys be used? | Medicine and dentistry. |
Where are transition metals found in the periodic table? | In the middle. |
What do the properties of transition metals make them useful for? | Building and construction. |
Why is copper a useful transition metal? | High conductivity. |
Why are scientists looking for new ways to extract copper? | Use less energy. |
Why are titanium and aluminium useful? | Resist corrosion. |
Why are aluminium and titanium expensive? | They need several stages and processes to be extracted which need a lot of energy. |
Why is recycling aluminium important? | We need to use less energy to extract 1kg of recycled than 1kg from ore. |
hat is crude oil? | A mixture of many compounds. |
What are many of the compunds in crude oil? | Hydrocarbons. |
What are hydrocarbons? | Compunds containing only hydrogen and carbon. |
What are alkanes? | Saturated hydrocarbons. Contain as much hydrogen as possible. |
What is the general formula for an alkane? | *=Subscript C*n*H*2n+2* |
How do we seperate crude oil into fractions? | Fractional distillation. |
What do the properties of each fraction depend on? | Size of molecules. |
Which fractions make better fuels? | Lighter. |
What are the products when we burn a hydrocarbon in air? | Carbon dioxide + Water |
What could produce pollutants when burning a fuel? | Impurities. |
How can we change products made when burning a fuel?? | Change conditions. |
What does burning fuels release? | Substances that spread throughout the atmosphere. |
What happens to substances in the atmosphere? | Some dissolve into water droplets, falling as acid rain. |
Name greenhouse gases. | Carbon dioxide, water |
What do greenhouse gases do? | Reduces rate at which energy is lost by the surface of the Earth by radiation. |
How might pollution produced by burning fuels be reduced? | Treating products of combustion. |
Which substances could be removed by treating products of combustion? | Nitrogen oxides, sulfur dioxide, carbon monoxide. |
What is cracking? | Splitting large hydrocarbon molecules into smaller ones. |
How do you 'crack' hydrocarbons? | Heat long hydrocarbons and pass gas over a catalyst. |
What does cracking produce? | Unsaturated hydrocarbons. Alkenes. |
What is the general formula for an alkene? | C*n*H*2n* |
How do you test for an unsaturated substance? | Turns bromine water colourless. |
Do alkenes burn? | Yes. |
What are plastics made of? | Polymers. |
What are polymers? | Large molecules made when monomers join together. |
What affects the properties of polymers? | The monomers they are created from. |
What affects the type of polymer produced? | Changing reaction conditions. |
What are the advantages of polymers? | New polymers are being developed with properties that make them suited for certain purposes. |
What are smart polymers? | Polymers that may have their properties changed by light, temperature or other changes in their surroundings. |
How are vegetable oils extracted? | From plants by pressing or distillation. |
Why are vegetable oils important? | They are important foods. |
What do all unsaturated oils contain? | Carbon - Carbon double bond. |
Why are vegetable oils useful in cooking? | High melting points. |
How are the boiling points of vegetable oils increased? | Hardening-(hydrogenation) |
What is hydrogenation? | Reacting a vegetable oil with hydrogen, breaking the double bond and making them saturated. |
What can be used to produce emulsions with special properties? | Oils. |
What are emulsions made from vegetable oils used for? | Foods such as salad dressings and ice cream. |
Why do we use additives? | To improve foods appearance, taste, and shelf life. |
Name some additive types. | Colours, preservatives, antioxidants, emulsifiers, stabilisers, thickeners, acidity regulators flavourings. |
How can you identify additives? | Chromatography. |
What can vegetable oils be used for other than cooking? | Burned as fuels. |
What are the advantages of using vegetable oil as a fuel? | Renewable. |