Topic Menu

Cyber-chess a chess instruction site
Solutions: Atomic Structure

Q13.

(a) The table below contains data for four different nuclei, P, Q, R and S.

Nucleus
Number of neutrons
Nucleon number (or mass number)
Number of protons - proton number
proton number nucleon number
P
5
11
6
0.55
Q
6
11
5
0.45
R
8
14
6
0.43
S
9
17
8
0.47

 

Adding the extra columns to the table enables you to work out the answers easily... it also shows the examiner you know what you are doing!

(i) Which nucleus contains the fewest protons? Q

(1 mark)

(ii) Which two nuclei are isotopes of the same element? P and R

(1 mark)

(iii) State and explain which nucleus has the smallest specific charge.

R

Specific charge is the charge per kg. As protons and nuetrons have approximately the same mass, in this means you can compare specific mass by dividing the mass mumber by the proton number - 6/14 is the smallest fraction or 0.43 is the smallest ratio - obtained from the table.

(2 marks)

(Total 4 marks)