(a)(i) Mention two types of bond present in the ammonium ion
(ii) Give three characteristic properties of electrovalent compounds
(iii) State. two differences between chemical reactions and nuclear reactions
(b) Two elements represented by the letters and Y have atomic numbers 9 and 12 respectively.
(i) Write the electronic configuration of X using the s,p,d, notation
(ii) To what group does Y belong in the periodic table?
(iii) Write the formula of the compound formed when X copibines with Y
(iv) Explain wily X is a good oxidizing agent
(v) State with reason, whether Y would be expected to form acidic or basic oxide
(c) Balance the following nuclear equations and identify the particles represented by X and Y.
(i) \(^{14}_6C\) \(\to\) X + \(^{14}_7N\)
(ii) \(^{14}_7C\)
Y \(\to\) \(^1_1H\) + \(^{17}_8O\)
(d) Consider the following list of substances: Carbon (IV) oxide, hydrogen, zinc, sulphier, methane, potassium and mercury. From the list above, state the:
(i) elements that are metals
(ii) compounds that are gases at room temperature
(iii) non-metals that are solids at room temperature
Explanation
(a)(i) Covalent bond and dative or co-ordinate covalent bond.
(ii) The characteristics are:
—They have high melting point or boiling point.
—They conduct electricity when molten or in solution
—They exist as aggregates of ions
—They are soluble in polar solvent e.g water and insoluble in non-polar solvents
(iii) State two differences between chemical reactions and .
|
Chemical reactions |
Nuclear reactions |
|
It involves (orbiting) electrons |
It involves nuclear particles |
|
It does not produce entities or there is no change in atomic number |
It results in the production of new nuclides or there is a change in atomic number |
|
Is not accompanied with great heat changes. |
It is accompanied with evolution of a lot of heat |
|
The rate is affected by external factors such as pressure, temperature, etc. |
The rate is not affected by the external factors. |
b)(i) 1s\(^2\)2s\(^2\)2P\(^2\)
(ii) Group (II) or alkaline earth metal
(iii) YX\(_2\)
(iv) X is a good oxidizing agent because its outer shell contains seven electrons, it therefore accepts one electron to form an octet structure. From the efinition of an oxidizing agent, oxidizing agents are good acceptors of electrons.
(v) Y (1s\(^2\)2s\(^2\)2p\(^6\)3s\(^2\)) would be expected to form a basic oxide because Y is a metal or Y is an electropositive element.
c)(i) \(^{14}_6C\) \(\to\) \(^0_1X\)+ \(^{14}_7N\)
X is a beta particle
(ii) \(^{14}_7N\) + \(^4_{-1}Y\) \(\to\) \(^1_1H\) + \(^{17}_8O\)
Y is an alpha particle
d)(i) Metals are zinc, potassium and mercury
(ii) Compounds that are gases at room temperature are carbon (IV) oxide and methane
(iii).Non-metal that is solid at room temperature is sulphur. ,