(Associativity ) Let `f: A to B , g : B to C " and " h: C to `. Then prove that ( h o g) o f = h o ( g o f )`

Explanation

(i)`P_(4)(s)+3NaOH(aq)+3H_(2)O(l)rarrPH_(3)(g)+3 NaH_(2)PO_(2)(aq)`
(ii)` 3N_(2)H_(4)(g)+4CIO_(3)^(-)(aq)rarr6NO(g)+4CI^(-)(aq)+6H_(2)O(l)`
(iii)`CI_(2)O_(7)(g)+4H_(2)O_(2)(aq)+3H_(2)O_(2)(aq)rarr2CI_(2)^(-)(aq)+4O_(2)(g)+5H_(2)O(l)`
(iv)`2cr(OH)_(4)^(-)(aq)+2OH^(-)(aq)+3H_(2)O_(2)(aq)rarr2CrO_(4)^(-)(aq)+4 O_(2)(g)+5H_(2)O`
`(v)4Zn(s)+3NO_(3)^(3)(aq)+7H_(2)O(l)rarr4Zn^(2+)(aq)+NH_(4)^(+)(aq)+10 OH^(-)(aq)`
(vii)`PbO_(2)(s)+CI^(-)(aq)+H_(2)O(l)+OH^(+)(aq)rarr8AI(OH)_(4)^(-)(aq)+3NH+(3)(g)`
(viii)`2Bi(OH)_(3)(s)3SnO_(2)^(-)(aq)rarr2Bi(s)+3SnO_(3)^(2-)(aq)+3H_(2)O(l)`
(ix)`2Bi(OH)_(3)(s)+3SnO_(2)^(2-)(aq)rarr2Bi(s)+3SnO_(3)^(2-)(aq)+3H_(2)O(l)`
(x)`2Cr(s)+3CIO_(4)^(-)(aq)+3H_(2)Orarr2Cr(OH)_(3)(s)+3CIO_(3)^(-)(aq)`