Chemistry: Electronic Configuration and Ionic Compounds

Electronic Configuration of Elements

• Chlorine has 7 electrons in its outermost shell and requires one more electron to complete its octet.
• The electronic configuration of chlorine is 2, 8, 7.
• The electronic configuration of other elements can be found in Table 3.3.

Formation of Ionic Compounds

• Sodium and chlorine react to form an ionic compound, NaCl.
• Sodium loses an electron to form a cation, Na+, while chlorine gains an electron to form a chloride anion, Cl-.
• The resulting ionic compound has a unit negative charge.

Properties of Ionic Compounds

• Ionic compounds are solids and are somewhat hard due to the strong force of attraction between the positive and negative ions.
• They are generally brittle and break into pieces when pressure is applied.
• Ionic compounds have high melting and boiling points due to the strong inter-ionic attraction.
• Electrovalent compounds are generally soluble in water and insoluble in solvents such as kerosene, petrol, etc.
• Ionic compounds conduct electricity through a solution involving the movement of charged particles.

Refining of Metals

• The most widely used method for refining impure metals is electrolytic refining.
• Electrolytic refining involves making the impure metal the anode and a thin strip of pure metal the cathode.
• A solution of the metal salt is used as an electrolyte.
• On passing electric current, the pure metal from the anode dissolves into the electrolyte, and an equivalent amount of pure metal from the electrolyte is deposited on the cathode.
• Soluble impurities go into the solution, while insoluble impurities settle down at the bottom of the anode and are known as anode mud.

Learn about the electronic configuration of elements such as chlorine and the formation of ionic compounds through the reaction of sodium and chlorine.