Oxygen And Oxides Flashcards
In dry air it is … % nitrogen
78.1
I’m dry air it is … % oxygen
21
In dry air it is … % Argon
0.9
In dry air it is … % Carbon Dioxide
0.04
Show that air is 1/5 oxygen using copper how?
Two gas syringes, containing 200cm of air, which is pushed back and forth over heated copper. Upon cooling, there should be 79cm or air
When using copper to show that air is 1/5 oxygen, beware…
Allow the air to cool down
Take the volume of the connecting tubes into account
Using the rust ion of Rio to show that air is 1/5 oxygen
Invert a test tube of iron wool into a beaker of water and mark the level of the water. Remark the level in a few days and fill the tube with water to determine what percentage of the air was lost
Burning phosphorous to show that air is 1/5 oxygen
Put a bell jar into a beaker of water and touch the phosphorous with a hot metal rod to ignite a reaction with oxygen. Using the same method see how many % the water level rose by
Reaction of phosphorous in oxygen
P4 + 5O2 = P4O10
Make oxygen in the lab by…
Catalytic decomposition (splitting up using a catalyst) of hydrogen peroxide
Equation for catalytic decomposition of hydrogen peroxide
2H2O2(aq) = 2H2O(l) + O2(g)
Magnesium reacts with oxygen with a … Flame
Bright white
Magnesium reacts with oxygen to produce…
White, powdery magnesium oxide (base)
Equation for reaction of magnesium and oxygen?
2Mg(s) + O2(g) = 2MgO(s)
Sulphur burns with a … Flame on oxygen
Blue
When sulphur burns in oxygen, … Is produced
Poisonous, colourless sulphur dioxide
SO2 is a … Oxide
An acidic
Equation for reaction between sulphur and oxygen
S(s) + O2(g) = SO2(g)
Flame Carbon burns in oxygen with a …
Depending on the purity, a small yellow-orange flame may be produced
Carbon burns in oxygen if…
Heated strongly
Carbon burns in oxygen to give
Colourless Carbon dioxide
Equation for Carbon burning in oxygen?
C(s) + O2(g) = CO2(g)
How do you make CO2 in the lab?
The reaction between dilute hydrochloride acid and calcium carbonate in the form of marble chips
Equation for reaction of dilute HCL and calcium carbonate
CaCO3(s) + 2HCl(aq) = CaCl2(aq) + CO2(g) + H2O(l)
Form Carbon dioxide by thermal decomposition of…
Metal carbonates
When heating metal carbonates you get…
Metal Carbonate = Metal Oxide + Carbon Dioxide
Some equipment you need to show how CO2 is produce from thermal decomposition
Bunsen
Test Tube over bunsen (holding metal carbonate)
Delivery Tube into test tube full of limewater
Clamp etc
How do you test for CO2
It turns limewater cloudy
Uses of CO2
Fire Extinguishers (when water is not used I.e. Electrical) as it is denser than air. Carbonated drinks at it dissolves in high pressure but when the top is opened the pressure falls and the gas bubbles out of the bottle
Properties of CO2
Colourless Gas
Denser than air
Slightly soluble in water
When Carbon dioxide reacts with water … Is produced
Carbonic Acid
The reaction of carbon dioxide and water can be reversed by…
Heating or boiling the product
Carbonic Acid is what strength
Weak
Equation for reaction of Carbon Dioxide and Water?
CO2(aq) + H2O(l) = H+(aq) + HCO3-(aq)
This is reversible so the equals sign is reversible
Sulphur dioxide reacts with water to form…
Sulphurous Acid
Sulphurous Acid is what strength?
Weak
Equation for sulphur dioxide reacting with water
H2O(l) + SO2(g) = H2SO3(aq)
Acid Rain is caused when…
Oxygen and water in the atmosphere react with sulphur dioxide to produce sulphuric acid (H2SO4) or with various oxides of nitrogen to give nitric acid (HNO3)
Sulphur dioxide and various oxides of nitrogen are produced…
Mainly from power stations, burning fossil fuels, motor vehicles, etc
Acid rain is damaging in that it…
Kills trees and makes lakes acidic so that they cannot support life. They also ‘attack’ limestone and some metals such as iron
To reduce acid rain we can…
Remove sulphur from fuels, use catalytic converters in cars and ‘scrub’ the gas from power stations to remove the oxides.
Catalytic converters…
Help convert nitrogen oxides into harmless nitrogen gas but they have no effect on sulphur dioxide