Chemical Reactions Flashcards
Chemical Reaction
when the particles of reactants collide with sufficient activation energy to create a whole new substance with a new set of properties
acid + base
salt + water
acid + metal
salt + hydrogen gas
Air consists of…
Nitrogen (78%) Oxygen (21%) Argon ( <1%) Carbon Dioxide (0.03%) Water Vapour (0.4%)
Carbon Dioxide Properties
Gas Colourless Acidic Odourless Heavier than air
Test for Carbon Dioxide
carbon dioxide turns limewater from clear to milky
Baking Soda + Vinegar
Gas
Catalyst
alters the rate of a reaction without being used up in the reaction
Oxygen Properties
Gas Colourless Odourless Tasteless Neutral Supports Combustion
Test for Oxygen
a glowing splint relights
Enzymes
biological catalysts
How do catalysts alter the rate of reaction?
they lower the activation energy
biochemical reaction
a chemical reaction taking place inside living cells
What factors affect the efficiency of enzymes?
temperature, pH and concentration
Rate of Reaction
the change in concentration per unit time of any one reactant or product
Factors affecting the rate of reaction
- types of reactants
- particle size
- concentration
- temperature
- catalysts
Nature of Reactants
Some bonds are easier to break or form than others
Particle Size
The more finely divided a solid, the greater the surface area exposed, the faster the reaction.
Conditions needed for a dust explosion to occur
- Combustible dust particles
- Source of ignition
- Dryness
- Sufficient Oxygen
- Enclosed spaces
Concentration
With greater concentration, there is a greater number of particles which collide more often and the rate of reaction is faster
Temperature
The higher the temperature the faster the rate of reaction. - As temperature increases, particles have more energy therefore they will move around and collide more often.
Example of biochemical reactions
- Photosynthesis
- Respiration
- Digestion
Activation Energy
The minimum energy that colliding particles must have for a reaction to occur
Effective Collision
The collision of reactants which results in the formation of products
