Chemical Reactions Flashcards
State what happens in all chemical reactions.
A new substance is formed.
Name 4 signs of a chemical reaction taking place in their chemical names.
Exothermic (releases heat), Endothermic (takes in heat), precipitation (solid forming), gas released (effervescence)
Describe what is meant by the rate of reaction.
The reaction rate is the rate at which a product is formed in a chemical reaction.
Name 4 ways to speed up the rate of a reaction.
Increasing temperature, using a catalyst, decrease particle size, increase concentration.
State what a catalyst is.
A catalyst is a substance that speeds up a reaction but isn’t used up during it.
Describe how the progress of a chemical reaction can be followed.
The progress of a chemical reaction can be followed by looking at the volume of gas (gas syringe), change in mass (weight), measuring cylinder (water).
Describe the curve on a rate graph as the reaction begins, and as it ends.
At the start point of a reaction, the reaction is the fastest (Curve is the steepest), at the endpoint of a reaction, the reaction is the slowest (Curve goes flat).
What is true about the speed of a reaction when the curve on a rate graph is steeper?
The rate of reaction is faster.
What is meant by average rate?
The average rate of a chemical reaction is calculated by the formula = △Q/△T Which means Change in quantity/Change in time.
What happens to reaction rate over time?
Over time, the reaction rate decreases.
