Required practical 7a - Rate measurements

Question 1

Measuring the volume of insoluble gases

Answer 1

the gas may be collected underwater in an inverted measuring cylinder

Question 2

Measuring the volume of soluble gases

Answer 2

may be collected in a gas syringe connected to a sealed vessel

Question 3

When can’t the change in mass of gases be measured?

Answer 3

not suitable for gases with a low mass

Question 4

How to measure the change in mass of a gas

Answer 4

continually weigh the conical flask the experiment is taking place in to calculate the change in mass

Question 5

Measuring change in a reactant or product by titration

Answer 5

sometimes samples of the reaction mixture are quenched then titrated to find the concentration of the reactant or product for comparison

Question 6

Measuring a coloured reactant or product

Answer 6

• colorimeter measures the colour intensity of a solution

- a calibration curve should be created with known concentrations of the reactant or product for comparison

Question 7

Finding the order of reaction only works when

Answer 7

-there is one reactant
or
-the other reactants are in large excess

Question 8

Shape of concentration-time curve in determining the order of reaction

Answer 8

0 order = straight
1st order = curved
2nd order = more curved