C3 Chemical Reactions
No description yet. This curated deck is ready for daily study.
Card preview (24)
Exothermic
Gives out energy. Usually in the form of heat, is shown with a rise in temperature.
Exothermic Example
Burning Fuels.
Endothermic
Takes in energy. Usually in the form of heat, is shown with a fall in temperature.
Endothermic Example
Thermal Decomposition.
Bond Breaking
Requires energy, so is Endothermic. Energy required to break bonds is greater than energy used in breaking old bonds.
Bond Making
Energy is released when formed, is Exothermic. Energy released is greater than energy used in breaking old bonds.
Specific Heat Capacity (SHC)
Amount of energy required to raise the temperature of 1 gram of a substance by 1 celcius.
Calorimetric
An experiment involving heating water by burning liquid fuel.
Energy given out per gram
Energy Released / Mass of Fuel Burnt.
Example of a Slow Reaction
Rusting
Example of a Fast Reaction
Explosion
How could you measure gas production?
Change in mass, or Gas Syringe.
Reaction Rate
The speed of reatants being turned into products.
Collision Frequency
How often particles collide during a reaction. More collisions - Higher reaction rate.
Energy Transfer during Collision
Particles need enough energy for a collision to be successful.
Yield
The amount of product you get from a reactant.
Limiting Reactant
The reactant which runs out first, stopping the reaction.
Excess Reactant
The other reactant which didn’t stop the reaction - some of this left.
Higher Temperature
Increases Reaction Rate (Faster)
Higher Concentration
Increases Reaction Rate (Crowded)
More Surface Area
Increases Reaction Rate (Reachability)
Catalyst
Increases Reaction Rate, by facilitating a surface for reactants to stick to. Increases successful collisions not collision frequency.
Relative Atomic Mass
Total atomic mass of an element
What is spectroscopy?
The study of the colour of flame given off by a substance when it is heated. Certain elements produce distinctly coloured flames when heated, which in turn create line spectra. This could aid with the discovery of new elements. Lithium - Red , Sodium - Orange , Potassium - Lilac