Different Types of Chemical Reactions (Part 1) Unit 2 Topic 3 Flashcards
What are the signs that a chemical reaction is taking place? (4)
Colour change
Formation of a precipitate
Gas production
Temperature change
What is an exothermic reaction?
What is an endothermic reaction?
Gives out energy
Takes in energy
Define combustion of fuels
Example equation
Reaction of a fuel with oxygen that produces at least 1 oxide & releases energy (Burning)
Fuel + oxygen 0-> CO2 + H2O + heat
Define neutralisation
Ionic equation
When acid & alkali react, hydrogen & hydroxide ions form water which is neutral.
H+ (aq) + OH- (aq) -> H2O (l)
Define displacement Example equation (zinc + copper)
More reactive element displaces less reactive metal from its compound.
Zinc + CuSO4 -> Zinc sulfate + copper
Define thermal decomposition Example equation (CaCO3)
Breaking down of a compound using heat Calcium carbonate (s) -> CaO (s) + CO2 (g)
Define cracking
Reaction used to break large hydrocarbon molecules into smaller molecules
Photosynthesis symbol equation
Light + 6CO2 + 6H2O -> C6H12O6 + 6O2
What type of process is bond breaking?
What type of process is bond making?
Endothermic
Exothermic
Symbol equation for methane and oxygen?
CH4 (g) + 2O2 (g) -> CO2 (g) + 2H20 (g)
What type of reaction is burning methane + why?
Exothermic because energy required to break reactant bones (CH4 + O2) is less than energy required to form bonds of products (CO2 + H20)
4 types of energy given off as a result of a chemical reaction?
Light, heat, sound & electricity
Exothermic or endothermic?:
- NaOH + H2SO4
- BaOH + NH4SCN
Exothermic
Endothermic
What colour is copper carbonate?
What colour is copper oxide?
Green
Black
What do metal carbonates thermally decompose into?
Metal Oxide + Carbon Dioxide
What is another word for calcium carbonate?
What is another word fir calcium oxide?
Limestone
Quick Lime
Label diagram of lime kiln.
SEE NOTES
What colour is calcium carbonate?
What colour is calcium oxide?
White
White
What are the uses for limestone? (2)
Blast Furnace
Neutralising soil
What are the uses for calcium oxide? (2)
Mixed with water to produce limewater
Make plaster
Equation:
CaO + H20
CaO + H2O -> Ca(OH)2
How is limestone used in the blast furnace to produce calcium oxide?
Limestone added to blast furnace during extraction of iron from its ore. Thermally decomposes to calcium oxide. CaO combines with acidic impurities (SiO2) removing them.
Equation:
CaO + SiO2
CaO + SiO2 -> CaSiO3
Equation:
Calcium oxide + silicon dioxide
Calcium Oxide + Silicon Dioxide -> Calcium Silicate (slag)
Advantages of limestone quarrying? (3)
Provides jobs
Boosts economy
Provides raw material
Disadvantages of limestone quarrying? (3)
Eye sore
Noise/dust pollution
Ruins animal habitats
