(a) Write down the electronic configuration of (i) sodium atom, and (ii) chlorine atom.
(b) How many electrons are there in the outermost shell of (i) a sodium atom, and (ii) a chlorine atom?
(c) Show the formation of NaCl from sodium and chlorine atoms by the transfer of electron(s)
(d) Why has sodium chloride a high melting point?
(e) Name the anode and the cathode used in the electrolytic refining of impure copper metal.
(a) Write down the electronic configuration of (i) sodium atom, and (ii) chlorine atom.
(b) How many electrons are there in the outermost shell of (i) a sodium atom, and (ii) a chlorine atom?
(c) Show the formation of NaCl from sodium and chlorine atoms by the transfer of electron(s)
(d) Why has sodium chloride a high melting point?
(e) Name the anode and the cathode used in the electrolytic refining of impure copper metal.
(a) Electronic configuration of Sodium (Na) atom whose atomic number =11
K shell - 2
L shell - 8
M shell - 1
Electronic configuration of Chlorine (Cl) atom whose atomic number =17
K shell - 2
L shell - 8
M shell -7
(b) (i) 1
(ii) 7
(c) The atomic number of sodium(Na) is 11 and electrons in the last shell is 1. The atomic number of chlorine(Cl) is 17 and electrons in the last shell is 7. So Na gives 1 electron to chlorine.
This is a complete transfer of electrons so it is an ionic compound.
(d) Sodium chloride has a high melting and boiling point. There are strong electrostatic attractions between the positive and negative ions, and it takes a lot of heat energy to overcome them. Ionic substances all have high melting and boiling points.
Sodium chloride consists of sodium ion (Na+) and chloride ion (Cl−). These are strongly attracted towards each other to form an ionic bond. To break this strong force of attraction between them, a large amount of energy is required. Hence, sodium chloride has a high melting point.
(e) The anode is made up of impure copper and the cathode is made up of pure copper and the electrolyte is copper sulphate solution.
(a) Electronic configuration of Sodium (Na) atom whose atomic number =11
K shell - 2
L shell - 8
M shell - 1
Electronic configuration of Chlorine (Cl) atom whose atomic number =17
K shell - 2
L shell - 8
M shell -7
(b) (i) 1
(ii) 7
(c) The atomic number of sodium(Na) is 11 and electrons in the last shell is 1. The atomic number of chlorine(Cl) is 17 and electrons in the last shell is 7. So Na gives 1 electron to chlorine.
This is a complete transfer of electrons so it is an ionic compound.
(d) Sodium chloride has a high melting and boiling point. There are strong electrostatic attractions between the positive and negative ions, and it takes a lot of heat energy to overcome them. Ionic substances all have high melting and boiling points.
Sodium chloride consists of sodium ion (Na+) and chloride ion (Cl−). These are strongly attracted towards each other to form an ionic bond. To break this strong force of attraction between them, a large amount of energy is required. Hence, sodium chloride has a high melting point.
(e) The anode is made up of impure copper and the cathode is made up of pure copper and the electrolyte is copper sulphate solution.
