C7 - Chemical Reactions Flashcards
What are 5 factors that can be changed to alter the rate of a chemical reaction? [5]
Temperature / concentration of solutions / pressure of gases / surface area of solids / catalyst
What two things are needed for a chemical reaction to happen (in terms of particles? [2]
Particles need to collide / particles need to have enough energy
Describe two main ways that the rate of reaction can be measured for a reaction that produces a gas [2]
Volume of gas produced / loss of mass
Explain the effect of increasing the temperature on the rate of reaction [4]
Rate of reaction increases… particles have more kinetic energy… more frequent collisions… more successful collisions
Explain the effect of increasing the concentration / pressure on the rate of reaction [3]
Rate of reaction increases… more particles per unit volume…more frequent collisions
Explain the effect of increasing the surface area on the rate of reaction [3]
Rate of reaction increases… more particles exposed to react… more frequent collisions
What is a catalyst? [2]
A substance that speeds up the rate of a reaction but is unchanged at the end of the reaction
Explain the effect of a catalyst on the rate of reaction [4]
Rate of reaction increases… provides an alternative reaction pathway… with lower activation energy… more particles have enough energy to react
Describe oxidation and reduction in chemical reactions [2]
Oxidation is the gain of oxygen / reduction is the loss of oxygen
Describe oxidation and reduction in a redox reaction [2]
OILRIG - Oxidation is loss of electrons / reduction is gain of electrons
What is an oxidising agent? [2]
A substance which oxidises another substance during a redox reaction - it will be reduced in the reaction
What is a reducing agent? [2]
A substance that reduces another substance during a redox reaction - it will be oxidised in the reaction
