Rate Of Reaction

Question 1

The rate of reaction depends on what four things?

Answer 1

1) temperature
2) catalyst
3) concentration
4) surface area of solids

Question 2

What four things can be a cause of an increased rate?

Answer 2

1) increase in temperature
2) increase in concentration
3) catalyst added
4) solid reactant crushed up into smaller bits

Question 3

What are three ways used to measure the rate of a reaction?

Answer 3

1) precipitation
2) change in mass
3) The volume of the gas given off

Question 4

What is the equation for the rate of reaction?

Answer 4

Rate of reaction=

Amount of reactant used or amount of product formed

____________________________

Time

Question 5

What is precipitation?

Answer 5

This is when the product of the reaction is it precipitative which clouds the solution

Question 6

Through using precipitation how can you measure the quickness of the reaction?

Answer 6

1) observer mark to the solution and measure how long it takes for it to disappear the quicker the mark disappears the quicker the reaction

Question 7

Why doesn’t precipitation work on all solutions to measure the rate of reaction?

Answer 7

Precipitation only works for reactions where the initial solution is rather see through

Question 8

What is the problem with the results of precipitation?

Answer 8

The result is very subjective- different people might not agree over the exact point when the mark disappears

Question 9

How can you Measure the rate of reaction using the change in mass?

Answer 9

Through measuring the gas given off

Question 10

Why are measuring the speed of a reaction that produces a gas what can this be carried out on?

Answer 10

A mass balance

Question 11

How does the mass balance work in measuring the speed of a reaction that produces gas?

Answer 11

As the gases are released the mass disappearing is easily measured on the balance. The quicker the reading on the balance drops the faster the reaction

Question 12

I would of precipitation, change in mass and the volume of gas given off, which method is more accurate in measuring the rate of reaction?

Answer 12

Change in mass through using a mass balance

Question 13

How is measuring the rate of reaction through the change in mass the most accurate method? Name a disadvantage

Answer 13

Because the mass balance is very accurate but he has the disadvantage of releasing the gas straight into the room

Question 14

What is involved to measure the rate of reaction through the volume of gas given off?

Answer 14

This involves the use of a gas syringe to measure the volume of gas given off. The more gas given off during a given time interval the faster the reaction

Question 15

Given advantage and disadvantage of using the volume of a gas given off as a method of measuring the rate of reaction

Answer 15

Advan- gas syringes usually give volumes accurate to the nearest millimetre, so they are quite accurate

Disad- if the reaction is to vigourous you can easily blow the plunger out of the end of the syringe

Question 16

What is the big disadvantage of using the mass balance in terms of the flask?

Answer 16

If the flask is to hot you will lose mass by evaporation as well as in the reaction

Question 17

What does the reaction of hydrochloric acid and marble chips demonstrate?

Answer 17

This experiment is is to demonstrate the effect of breaking the solid up into small bits

Question 18

What is the reaction of magnesium metal with dilute HCI used to determine?

Answer 18

Used to determine the effect of concentration

Question 19

What does the decomposition of hydrogen peroxide show?

Answer 19

This experiment looks and have a catalyst affects the rate of reaction

Question 20

Give an example of a reaction that happens very slowly and one that is very fast

Answer 20

The corrosion of Arjen is a reaction that happens very slowly.
Explosions are very fast reactions

Question 21

Give three ways of increasing the rate of reaction between magnesium and sulphuric acid

Answer 21

Increase the temperature of the acid

Use smaller pieces

Increase the acid concentration

Use a catalyst

Question 22

Describe one way of monitoring a reaction in which gas is given off

Answer 22

Measure the volume of gas given off by collecting it in a gas syringe

Or monitor the mass of a reaction flask from which the gas escapes

Question 23

How would reducing the concentration of an acid affect the time taken for a piece of zinc to react with it?

Answer 23

It would increase the time taken which would reduce the rate of reaction

Question 24

Oxidation of lactose in milk makes it go sour. How could this reaction be slowed down?

Answer 24

By keeping the milk cool such as storing it in the fridge