Q16 of 27 Page 1

(a) List in tabular form 3 chemical properties on the basis of which we can differentiate between a metal and a non-metal.

(b) Give reasons for the following:


(i) Most metals conduct electricity well.


(ii) The reaction of iron(II) oxide [Fe2O3] with heated aluminium is used to join cracked machine parts.


a)


b i)The outer electrons of metal atoms are not tied to any one atom. Therefore, these electrons are free to move within the structure of a metal when an electric current is applied. So, metals make good conductors.


ii) The reaction taking place between Fe2O3and aluminium is a thermite reaction. In such a reaction, a large amount of heat is produced i.e. this reaction is exothermic in nature. As a result of this large amount of heat, the metals produced are in molten form. So, the iron that will be produced will be in molten form and will join the cracked machine parts easily.

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