Topic 2 Reactions, NEED FOR YEAR 10 Flashcards
State 3 things oxygen is used for
- welding torches
- rocket fuel
- breathing apparatus in hospitals
Chemical tests for combustion products:
Water:
Carbon dioxide
Water- presence of water turns anhydrous copper sulfate from white to blue
Carbon dioxide- turns limewater milky
What is the equation for the preparation of oxygen?
Hydrogen peroxide + manganese dioxide -> water + oxygen
What is the test for oxygen?
We proved oxygen had been produced by using a glowing splint which relights.
What are the results (observations) of the oxygen test?
Bubbles of gas can be seen and the test tube empties.
When the glowing splint is put into the mouth of the test tube it relights
What is the conclusion of the oxygen test?
Oxygen is prepared by the decomposition of hydrogen peroxide
To speed this reaction up we used manganese dioxide. Manganese dioxide is a catalyst.
What is the definition of a catalyst?
A catalyst is a chemical that speeds up a reaction without being used up itself.
.
Fill in the blanks:
Oxygen is a….. And……. Gas. It makes up….of the mixture called air.
1-colourless
2-odourless
3-21%
What is hydrogen used for?
Making margarine
Clean fuel
Rocket fuel
List 2 properties of hydrogen
Hydrogen is a colorless and odourless gas.
What is the equation for the preparation of hydrogen?
Magnesium + Hydrochloric Acid → Magnesium Chloride + Hydrogen
What is the test for hydrogen?
The test for hydrogen is using a lighted splint, you will hear a squeaky pop.
What are the results (observations) when testing for hydrogen?
Heat given out
Bubbles of gas produced
SQUEAKY POP with a lighted splint
What is the conclusion when testing for hydrogen?
Hydrogen can be prepared by an acid with a metal.
How many people could the Hindenburg carry?
72
What year did the Hindenburg crash?
1937
What voyage did the Hindenburg disaster strike on?
It’s 63rd voyage
What gas was the Hindenburg filled with?
The hydrogen
List 2 properties of carbon dioxide
Carbondioxide is a colourless and odourless gas.
List some uses of carbon dioxide
Fizzy drinks
Fire extinguisher
Dry Ice
What is the equation for the carbon dioxide test?
Calcium carbonate + Hydrochloric acid → Calcium chloride + Water + Carbon Dioxide
What are the results (observations) for the carbon dioxide test?
Bubbles of gas
Metal carbonate disappears to give a clear solution
Lime water turns milky
Fill in the blanks:
Carbon dioxide can be prepared easily by reacting a….. carbonate with…..
Metal
Acid
What is the test and the result for:
Oxygen
Hydrogen
Carbon dioxide
Oxygen:
Test-glowing splint
Result-relights
Hydrogen:
Test-lighted splint
Result-squeaky pop
Carbon dioxide:
Test-bubble into limewater
Result-limewater turns milky
What do endothermic reactions do?
Take in heat
What is an example of an endothermic reaction?
An example of an endothermic reaction is sherbet dissolving on your tongue
What is an exothermic reaction?
It’s gives out heat
What is an example of an exothermic reaction?
An example of an exothermic reaction is burning a piece of wood
What is the definition of thermal decomposition?
Thermal decomposition is the BREAKING DOWN of a chemical using HEAT energy.
What is the equation of the thermal decomposition of copper carbonate?
Heat Copper carbonate (green) ---> copper oxide (black) + carbon dioxide
This reaction is endothermic
When does an oxidation reaction occur?
When a chemical reacts with oxygen
When does reduction occur?
Occurs when a substance loses oxygen
What is a reducing agent
a substance which reduces another substance
What is a redox reaction?
A reaction in which REDUCTION AND OXIDATION takes place together.
What is the thermite reaction equation?
iron(III) oxide + aluminium → aluminium oxide + iron
What percent of the air is nitrogen
78%
What percent of the air is argon
0.9%
What percent of the air is Co2
0.037%
Give the word equation for respiration
Sugar+oxygen->carbon dioxide + water (+energy)
Name the 2 products of the reaction when candle wax combusts
Water
Carbon dioxide
What is candle wax made up of
Of substances containing carbon and hydrogen
What are the chemicals required in the preparation of oxygen
Hydrogen peroxide and manganese dioxide
Give 2 examples of industrial catalysts
Iron and platnium
What is an enzyme
Enzymes are soluble protein molecules that can speed up chemical reactions in cells
Name some of the chemical reactions that enzymes are involved in
Respiration, photosynthesis and making new proteins
What are the chemicals required in the preparation of hydrogen
Hydrochloric acid and magnesium
What are the chemicals required in the preparation of carbon dioxide
Calcium carbonate and hydrochloric acid
What is the risk assessment in the prep of oxygen, hydrogen and carbon dioxide
Wear eye protection
Is hydrogen less dense than air
Yes
Is oxygen less dense than air
No
Is carbon dioxide less dense than air
No
Do you use and upward delivery with hydrogen
Yes
Do you use an upward delivery with oxygen
No
Do you use an upward delivery with carbon dioxide
No
Is hydrogen denser than air
No
Is oxygen denser than air
Slightly
Is carbon dioxide denser than air
Yes
Do you use a downward delivery with hydrogen
No
Do you use a downward delivery with oxygen
Yes
Do you use a downward delivery with carbon dioxide
Yes
What is hydrogens solubility in water
Very low
What is oxygens solubility in water
Low
What is carbon dioxides solubility in water
Low
Hydrogen overwater?
Yes
Oxygen overwater?
Yes
Carbon dioxide overwater?
Yes
What is the definition of oxidation
Addition of oxygen
What is the definition of reduction
Removal of oxygen
What is the definition of a redox reaction
Reduction and oxidation both taking place in reaction
What is being reduced and what is being oxidised in this equation:
Calcium+magnesium oxide->calcium oxide+magnesium
Calcium -> calcium oxide is oxidised
Magnesium oxide->magnesium is reduced
What colour is copper oxide
Black powder
What colour is carbon
Black powder
Rusting equation
Iron +oxygen + water –> hydrated iron oxide
Burning a fuel equation
Fuel + oxygen —> carbon dioxide + water (+energy)
Composition of air: What percentage of air is; Oxygen Nitrogen Argon Carbon dioxide
Oxygen - 21%
Nitrogen - 78%
Argon - 0.9%
Carbon dioxide - 0.037%
Give 4 physical properties of oxygen
Colourless, odourless gas, not very soluble on water, same density as air
Give the word equation for respiration
Sugar + oxygen —> carbon dioxide + water (+energy)
Describe a chemical test for water
Use the chemical anhydrous copper sulfate which changes colour from white to blue in presence of water
What chemicals are required in the preparation of oxygen
Hydrogen peroxide
Catalyst manganese dioxide
Give three examples of industrial catalysts.
Vanadium (V) oxide
Platinum
Iron
What is an enzyme
Enzymes are soluble protein molecules that can speed up chemical reactions in cells
Name some of the chemical reactions that enzymes are involved in.
DNA replication, protein synthesis, digestion
What is the special ingredient in ‘bio’ or ‘biological’ powders?
Biological enzyme
If there is a stain on someones shirt and the stain is removed by a 40° wash with ace bio powder, why was the stain not removed at a 70° and cold wash with ace bio powder
Not used at optimum temperature
What chemicals are required in the preparation of hydrogen
Magnesium
Hydrochloric acid
What gas are modern airships filled with
The gas was helium
Which nation were the first masters of airship technology and what were they used for?
Germany and the airships were used as bombers in the First World War
What were airships developed for after 1918
They were designed for passenger flights
What was Germany’s biggest airship called
The Hindenburg
What happened to the airship in 1937
The airship exploded and crashed
What was the chemistry of the Hindenburg disaster
Hydrogen reacted with oxygen
How many people died due to the Hindenburg disaster
36
What does the NASA scientist think caused the Hindenburg explosion
The airship was charged with static electricity and the flammable paint caught fire
What chemicals are required in the preparation of carbon dioxide
Hydrochloride acid and marble chips
Give two physical properties of carbon dioxide
Gas
Colourless / odourless
If in an experiment the initial temperature of a substance is 20° and the final temperature is 26°, what type of reaction has taken place
Exothermic
If in an experiment the initial temperature of a substance is 22° and the final temperature is 18°, what type of reaction has taken place
Endothermic
If in an experiment the initial temperature of a substance is 21° and the final temperature is 31°, what type of reaction has taken place
Exothermic
If in an experiment the initial temperature of a substance is 22° and the final temperature is 35°, what type of reaction has taken place
Exothermic
If in an experiment the initial temperature of a substance is 20° and the final temperature is 18°, what type of reaction has taken place
Endothermic
In an experiment we find out what happens when zinc is added to copper sulphate solution, give three pieces of evidence that tell you a chemical reaction is taking place. REMEMBER THE TEMPERATURE BEFORE WAS 18° AND THE TEMPERTAURE AFTER IS 25°
Temperature increases
Powder disappears and brown sludge appears
Liquid changes colour
Which of the following terms could be used to describe the reaction when zinc is added to copper sulphate solution, explain your answer: Exothermic Oxidation Decomposition Endothermic
Exothermic as the temperature increases during the reaction
What is being reduced and what is being oxidised in this equation:
Zinc oxide + hydrogen —-> zinc + water
Zinc oxide is being reduced
And the hydrogen is oxidised
What is being reduced and what is being oxidised in this equation:
Aluminium oxide + potassium —> aluminium + potassium oxide
Aluminium is being reduced
Potassium is being oxidised
Fill in the gaps:
In the Thermite reaction, the two reactants are…….. and………. The Thermite reaction is a very………… reaction as it gives out lots of heat. The reactant…………… is reduced to molten iron. This reaction was used to…….train tracks together.
Iron oxide Aluminium Exothermic Iron oxide Weld
After you have completed the practical heating a mixture of copper oxide and carbon answer the following questions:
A) What colour is copper oxide
B) what colour is carbon
C) what do you see when you heat the mixture
D) what do the contents of the boiling tube look like after heating
E) write an equation for the reaction
F) why is this reaction a redox reaction
A) black powder
B)black powder
C) mixture glows orange and has given off
D) coppery coloured, solid produced
E) copper oxide + carbon –> copper + carbon dioxide
F) The copper oxide is reduced to copper and the carbon is oxidised to carbon dioxide