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