Rate Of Reaction Flashcards
What effect does the concentration of an acid have on the rate of reaction?
The higher the concentration of acid, the higher the rate of reaction.
State 2 ways you can increase the rate of reaction…
Increase concentration
Increase temperature
Calcium carbonate + Hydrochloric acid= ……
Calcium chloride + carbon dioxide + water.
State a possible loss in mass in a rate of reaction experiment…
Gas (e.g. Co2) formed and lost.
What difference does the size of chips in a rate of reaction experiment make?
The smaller the chips the faster the rate of reaction (e.g. Powder is faster than big chips)
A chemical reaction occurs when reacting particles collide with sufficient energy. The reaction between marble and Hydrochloric acid is faster if the acid is at a higher temperature. Explain why…
Increase temp;
•increases KE of particles
•greater proportion of particles have KE > Ea
•more successful collisions per unit time i.e. Rate increases
If the volume of a substance in a rate of reaction experiment decreases each minute until is remain steady at a certain volume, what happens??
Concentration of acid decreases during the reaction and then after a certain time all the …… Has reacted with the …..
Explain why a reaction would far slower as time increased in terms of particles?
As the reaction continues the concentration of the acid decreases and particles brake up and form new product particles.
Adding a catalyst:
- lowers the activation energy, Ea
- a greater proportion of particles will have K.E greater than Ea
- a greater proportion of successful collisions per unit time
- I.e RATE INCREASES.
Give an example of a catalyst…
MANGANESE (IV) OXIDE
What is a catalyst?
A substance which speeds up the rate of reaction by providing an alternate pathway of lower activation.
How does the catalyst provide this alternate pathway of lower activation energy?
The catalyst must have WEAKENED the bonds in the hydrogen peroxide.
Give an explanation in terms of collision theory why an INCREASE in SURFACE AREA would INCREASE the RATE….
- Increasing surface area, increases number of reactant particles.
- This in turn increases the number of collisions
- which increases the number of successful collisions per unit time
What are the two possible outcomes of collision theory?
- ) bounce apart = no reaction
2. ) particles break up and form new product particles = a successful collision reaction.
For a reaction to occur, I.e a collision to be successful…
K.E needs to be greater than Ea
What is the link between surface area and rate?
The larger the surface area the faster the rate.
Give an example of how you could slow down the rate of reaction?
Use an acid of lower concentration.
What is the effect of the increase in concentration on the rate?
Higher concentration=higher rate
What is the effect of the increase in pressure of a gas on the rate?
Higher pressure=higher rate
What is the effect of the increase in surface area of a solid on the rate?
Bigger surface area= higher rate
What is the effect of the increase in tenperature on the rate?
Higher temperature = higher rate
What is the effect of the increase in catalyst(s) on the rate?
Catalysts increase the rate of reaction but don’t get used up in the reaction.
