EXTRA

Question 1

Explain why a fluoride ion (F-) is larger than a sodium ion (Na+)

Answer 1

-Fluoride ion has fewer protons
-weaker attraction between nucleus and outer e-

Question 2

describe how molecules are ionised using electron spray ionisation

Answer 2

-sample is dissolved
-passed through a high pressure nozzle
-each molecule gains a proton

Question 3

during the titration the student washed the inside of the conical flask with some distilled water
-suggest why this washing does not give an incorrect result

Answer 3

-does not change the number of moles

Question 4

Chlorine has a low boiling point because the forces between the molecules are weak.
Explain how these forces arise between molecules of chlorine.

Answer 4

-(Random) movement of electrons in one molecule (creates a dipole) /
a (temporary) dipole is formed in one molecule / an imbalance in
electron density in one molecule
Induces a dipole in a neighbouring molecule.
(These) temporary dipoles attract / temporary attraction between δ+
and δ–