(a)(i) What is the common name given to the group VII elements?
(ii) Name the hydrides of the first two elements in group VII.
(iii) State three chemical properties of group VII elements.
(b) Copy and complete the following table:
| Particles |
Number of Neutrons |
Number of electrons |
Number of prontons |
Mass Number |
| W\(^{2+}\) | 12 | 24 | ||
| X\(^{2+}\) | 8 | 16 | ||
| Y | 13 | 27 | ||
| Z | 12 | 11 |
(c)(i) Define each of the followinc processes: I. nuclear fission; II. nuclear fusion.
(ii) Give one use of each process in (c)(i).
(d)(i) List three types of radiation that are produced during radioactivity.
(ii) Arrange the radiations listed in
(d)(i) in order of increasing: I. penetrating power; II. ionizing power.
Explanation
(a)(i) The common name given to group VII elements is Halogens.
(ii) Hydrides of the first two elements in group VII: (1) Hydrogen fluoride (2) Hydrogen chloride.
(iii) Three chemical properties of group VII elements are: (1) High electron affinity/strong oxidation 4-gents/electron acceptor. (2) High electronegative (3) React with hydrogen to form acid. (4) Form salts with metals. (5) React with alkalis to form salts. (6) React with water to form acids. (7) Displacement of lower halogens from their acids/salts. (8) Reacts with hydrocarbons to form alkyl halids.
(b) Copy and complete the following table:
| Particles |
Number of Neutrons |
Number of electrons |
Number of prontons |
Mass Number |
| W\(^{2+}\) | 12 | 10 | 12 | 24 |
| X\(^{2+}\) | 8 | 10 | 8 | 16 |
| Y | 14 | 13 | 13 | 27 |
| Z | 12 | 11 | 11 | 23 |
(c)(i) Define the following processes: I. Nuclear fission – splitting of a heavy nucleus into smaller nuclei (of smaller mass) with release of (large amount of) energy and radiations. II. Nuclear fusion –combination of smaller nuclei to form a large nucleus with the release of (large amount of) energy and radiation.
(ii) Give one use of each process in (c)(I). I. Used to generate electricity/nuclear or hydrogen bomb/ production of new elements/production of radioisotopes. II. Used to produce nuclear weapon/ atomic or hydrogen bomb/production of new elements/production of radioisotopes.
(c)(i) List three types of radiation that are produced during radioactivity: (1) alpha (2) beta (3) gamma.
(d)(ii) Arrange the radiation listed in (d)(i) in order of increasing:
I. Penetrating power — \(\alpha\), < \(\beta\) < \(\gamma\)
II. Ionizing power — \(\gamma\) < \(\beta\) < \(\alpha\)