Differentiate between metal and non-metal on the basis of their chemical properties.
Metal | Non-metal |
Metals are electropositive. | Non-metals are electronegative. |
They react with oxygen to form basic oxides. $4 Na + O _{2} \longrightarrow 2 Na _{2} O$ These have ionic bonds. |
They react with oxygen to form acidic or neutral oxides. $C + O _{2} \longrightarrow CO _{2}$ These have covalent bonds. |
They react with water to form oxides and hydroxides. Some metals react with cold water, some with hot water, and some with steam. $2 Na +2 H _{2} O \longrightarrow 2 NaOH + H _{2} \uparrow$ |
They do not react with water. |
They react with dilute acids to form a salt and evolve hydrogen gas. However, $Cu ,\, Ag ,\, Au , \,Pt ,\,Hg$ do not react. $2 Na +2 HCl \longrightarrow 2 NaCl + H _{2} \uparrow$ |
They do not react with dilute acids. These are not capable of replacing hydrogen. |
They react with the salt solution of metals. Depending on their reactivity, displacement reaction can occur. $CuSO _{4}+ Zn \longrightarrow ZnSO _{4}+ Cu$ |
These react with the salt solution of non-metals. |
They act as reducing agents (as they can easily lose electrons). $Na \longrightarrow Na ^{+}+ e ^{-}$ |
These act as oxidising agents (as they can gain electrons). $Cl _{2}+2 e ^{-} \longrightarrow 2 Cl ^{-}$ |
You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Explain why these sour substances are effective in cleaning the vessels.
Give reasons why copper is used to make hot water tanks and not steel (an alloy of iron).
Which gas is produced when dilute hydrochloric acid is added to a reactive metal? Write the chemical reaction when iron reacts with dilute $H_2SO_4$.
What are amphoteric oxides? Give two examples of amphoteric oxides.
What chemical process is used for obtaining a metal from its oxide ?