Year 10 Term 1 Flashcards
How does zinc react with acid
Some bubbles, acid turns grey, some zinc has floated to the top, overtime zinc expands
How does iron react with acid
Lots of small bubbles rising to the surface, turns solution brown
How does cooper react with acid
No visible change
How does magnesium react with acid
Ferocious bubbling, steam produced, test tube hot to touch, turns solution cloudy
Extraction of iron
Wet match and role it in iron oxide
Bunsen burn about 1/3 of match, blow it out
Knock black ash into wayboat
Extraction of copper
Spatula of CuO in test tube
Spatula of Carbon is same test tube, shake
Put wool in top of test tube
Hold above Bunsen for 5 mins
Acid + metal oxide —>
Salt +water
Acid + hydroxide —>
Salt + hydrogen
Acid + carbonate
Salt + water + carbon dioxide
What is electrolysis
Process whereby an ionic substance that is molten or dissolved is broken down into elements using electricity
Is anode negative or positive and what does it attract
Anode is positive and attracts negative ions
Is cathode positive or negative and what does it attract
Cathode is negative and attracts positive ions
What happens if there are metal ions of low reactivity e.g copper, silver, gold and platinum ions
They are discharged instead of H+ ions because they are easier to discharge because less reactive
What percentage of nitrogen is there in the atmosphere
78%
What was the earth like 4600 million years ago
Ball of molten rock, when cooled formed volcanoes which produced CO2, ammonia, methane and steam
As earth cooled more steam condensed as rain forming oceans
No ozone layer so UV rays to intense for anyone to live
When did creatures evolve
2 billion years ago near underwater volcanoes as this was were the nutrients were
First organisms become algae which took up CO2 and produced oxygen
Took a long time to build up to a high level
What happened when the oxygen levels built up
Some reacted to form the ozone layer shielding the earth from harmful UV rays (1 billion years ago)
What happened half a billion years ago
Possible for organisms to live on land
Ammonia oxidised to nitrogen, methane levels dropped
Respiration carried out by animals producing CO2 and photosynthesis using it up and locking it up in sugars and producing oxygen
Does respiration produce CO2
Fill test tube with 2cm of limewater
Use straw, blow gently into limewater, continue until you see a change
Limewater will turn cloudy if O2 is present
Is CO2 acidic
Fill test tube with 2cm of distilled water
Add 2 drops of universal indicator noting colour change
Use straw and blow into solution until you see change
Solution will turn red/orange because CO2 is acidic
Describe greenhouse effect
Ultraviolet radiation (short wavelength) from sun warms earths surface then radiates infrared (longer wavelength). This radiation goes back into space resulting in cooling effect and some radiation reflected off earths atmosphere (greenhouse gases) keeping earth warm
What’s a carbon footprint
Make you leave on environment the more you use, the larger the carbon footprint
How to reduce carbon footprint
Walks more
Grown own fruit and veg
Recycle waste
Methane and carbon footprint
Second most abundant greenhouse gas cows release methane
Nitrous oxide and carbon footprint
Produced when bacteria in soil produce it. Problem because of increased use of nitrous based fertilisers
Effects of global climate change
Glaciers have shrunk, ice on rivers and lakes is breaking up earlier, loss of sea ice, trees are flowering earlier
How to prevent climate change
Chose renewable power
Buy organic and locally sourced food
Put waste in compost
Use buses or trains
What’s combustion
burning- exothermic reaction, complete combustion is a plentiful supply of air, where there is excess of oxygen
What’s incomplete combustion
Limited supply of air, produces carbon monoxide and water or carbon and water
Effects of products of combustion
Water vapour harmless in smaller amounts
CO2 is greenhouse gas
Carbon monoxide is toxic
Un burned carbon is a particulate that can get into your lungs
Where does crude oil come from
Fossils fuels and mud built up over millions of years increasing heat and pressure causing remains to brake down molecules that form crude oil and natural gas
Many compounds in crude oil only contain carbon and hydrogen called hydrocarbons
What are alkanes
Most common hydrocarbon which general formula CnH2n+2
Simplest alkane with formula
Methane CH4
H
|
H—C—H
|
HThe second simplest alkane with formula
Ethane C2H6
H H
| |
H—C—C—H
| |
H HThe third simplest alkane with formula
Propane C3H8
H H H
| | |
H—C—C—C—H
| | |
H H HThe fourth simplest alkane with formula
Butane C4H10
H H H H
| | | |
H—C—C—C—C—H
| | | |
H H H HWhat’s a molecular formula
Gives the number of atoms of each element in a molecule- nothing about the structure
What’s a structural formula
Shows the atoms Sargon by carbon with the attached hydrogens
What’s a displayed formula
Shows how all the atoms are arranged and all the bonds between them
What percentage of oxygen is there in the atmosphere
21%
What percentage of Nobel gases are there in the atmosphere
1%
What percentage of carbon dioxide water vapour is there in the atmosphere
0.03%
