Term
| Give one reason why scientists know the earth is older than 400 million years |
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Definition
| Radioactivity keep the earths core hot |
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Term
| Give two pieces of evidence that show South America was once joined to Africa |
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Definition
Any two from:
same shape
same rock types
same fossils |
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Term
| Give two pieces of evidence that helped to convince scientists that the earths crust is made up of moving tectonic plates |
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Definition
Any two from:
earthquakes
volcanoes
continental drift
oceanic ridges
formation of (new) mountain ranges
formation of (new) islands
tsunamis |
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Term
| What are the two most common gases in the atmosphere today |
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Definition
|
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Term
| How much oxygen is there in todays atmosphere |
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Definition
|
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Term
| How much nitrogen is there in todays atmosphere |
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Definition
|
|
Term
| What environmental problem does sulphur dioxide cause |
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Definition
|
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Term
| How can we reduce acid rain in coal fired power stations |
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Definition
| Use flue gas desulphurisation which uses limestone powder to neutralise the acid gases |
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Term
| What is the word equation for complete combustion |
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Definition
| fuel + oxygen --> carbon dioxide+ water |
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Term
| Why should carbon dioxide be prevented from entering the earths atmosphere |
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Definition
| It is a greenhouse gas that can cause global warming |
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Term
| What is the meaning of the term ore |
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Definition
| A rock that contains enough metal to make is economical to extract |
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Term
What type of reaction is this:
iron oxide + carbon --> iron + carbon dioxide |
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Definition
| reduction - the iron looses oxygen so is reduced |
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|
Term
Balance this symbol equation
Fe2O3 + C --> Fe + CO2 |
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Definition
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Term
| Give three differences between a pure metal and an alloy of a metal |
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Definition
| In a pure metal all the atoms are the same size and are able to slip or slide over each other making it soft.Different sized atoms in the alloy make the structure distorted or disrupted so it is difficult for layers of atoms to slip or slide over each other. |
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Term
| Explain why the recycling of iron is neccessary for sustainable development |
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Definition
conserves or saves resources or metal ores
saves energy resources
decreases waste materials |
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Term
| What type of fat contains double carbon carbon bonds |
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Definition
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Term
| What colour is the product when bromine water reacts with an unsaturated fat |
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Definition
| colourless (no marks for clear) |
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|
Term
| What colour is the product when bromine water reacts with a saturated fat |
|
Definition
| remains orange no reaction |
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Term
| What colour is the product when iodine water reacts with an unsaturated fat |
|
Definition
| colourless (no marks for clear) |
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|
Term
| What colour is the product when iodine water reacts with a saturated fat |
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Definition
| remains violet as there is no reaction |
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Term
| How do you harden unsaturated vegetable oils |
|
Definition
react it with hydrogen (hydrogenation)
heat at 60°C
use a nickel catalyst |
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Term
| What is the process that is used to detect and identify dyes in food colourings |
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Definition
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Term
| How do you separate a mixture of alkanes by fractional distillation |
|
Definition
heat or evaporate the crude oil to change it to a gas or vapour
cool or condense the hydrocarbons at different temperatures or boiling points |
|
|
Term
| what is the formula for methane |
|
Definition
|
|
Term
| what is the formula for ethane |
|
Definition
|
|
Term
| what is the formula for propane |
|
Definition
|
|
Term
| what is the formula for butane |
|
Definition
|
|
Term
| what is the formula for pentane |
|
Definition
|
|
Term
| what is the formula for hexane |
|
Definition
|
|
Term
| what is the formula for heptane |
|
Definition
|
|
Term
| what is the formula for octane |
|
Definition
|
|
Term
| What is the formula for ethene |
|
Definition
|
|
Term
| what is the formula for propene |
|
Definition
|
|
Term
| What is the formula for butene |
|
Definition
|
|
Term
| what is the formula for pentene |
|
Definition
|
|
Term
| what is the formula for hexene |
|
Definition
|
|
Term
| Why are lower carbon fractions in more demand that higher carbon fractions |
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Definition
| Lower carbon fractions burn more easily and are therefore used as fuels |
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Term
|
Definition
| a process used to break down large hydrocarbon molecules into smaller more useful ones |
|
|
Term
Complete this equation for cracking
C20H42 --> C16H34 + 2........ |
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Definition
| C20H42 --> C16H34 + 2C2H4 |
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Term
| Name three ways the oil industry can solve the problem of the C5-C8 fraction having low supply and high market demand |
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Definition
use lighter crude oils develop markets for low demand fractions
develop new techniques or equipment to use low demand fractions as fuels
cracking
convert low demand fractions to high demand fractions or bigger molecules to smaller molecules develop alternative or bio fuels |
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|
Term
| What is the general formula for an alkane |
|
Definition
|
|
Term
| What is the general formula for an alkene |
|
Definition
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