Chap 6 F4

Question 1

3 methods to determine end point of titration

Answer 1

1. indicator such as….
2. measure ph value
3. measure electrical conductivity

Question 2

2 effects of acid rain

Answer 2

1. reduce the acidity of water in lakes-kill the aquatic animals
2. increases acidity of soil -not fertile
3. corrode buildings

Question 3

2 ways to prevent acid rain

Answer 3

use alternative source of energy such as solar energy

-use catylytic coverter (filter air)

Question 4

Why aqueous ethanoic acid can conduct e but glacial cannot?

Answer 4

1.The ethanoic acid molecules in an aqueous solution ionise to form hydrogen ions and ethanoate ions.

treeth The ions enable the aqueous solution to conduct electricity.

• Glacial ethanoic acid exists as molecules

only.

• The absence of free ions in the glacial ethanoic acid causes it to be unable to conduct electricity.

Question 5

How voltaic cell with copper and zinc with (Ag no3 as electrolyte works)?

Answer 5

1.Cu more electropositive then copper

• As a result, copper undergoes oxidation by losing electrons to the silver electrode. • The half-equation for the reaction is

Cu Cu²+ + 2e¯

• Silver ion in the silver nitrate solution is reduced by receiving electrons at the silver electrode.

The half-equation for the reaction is

Ag+ e → Ag • The flow of electrons causes the voltmeter to register a reading