Potassium dichromate `(K_(2)Cr_(2)O_(7))` is an orange coloured compound , very frequently used in laboratory as an oxidising agent as well as in a redox titration. It is generally prepared from chromite `(FeCr_(2)O_(4))` ore according to the following reactions: (1) Fusion of chromite ore with sodium carbonate in excess of air. `FeCr_(2)O_(4) + Na_(2)CO_(3) + O_(2) rarr Na_(2)CrO_(4)+Fe_(2)O_(3) +CO_(2)` (2) Acidifing filtered sodium chromate solution with sulphuric acid. `Na_(2)CrO_(4) + H_(2)SO_(4) rarr Na_(2)Cr_(2)O_(7) + Na_(2)SO_(4) + H_(2)O` (3) Treating sodium dichormate with potassium choride . `Na_(2)Cr_(2)O_(7) + KCl rarr K_(2)Cr_(2)O_(7) + NaCl` If whole of the chormite ore given in the previous question gets consumed and sufficient amount of rest of the reactants are given, then the mass of `K_(2)Cr_(2)O_(7)` obtained is:A. 14.7 gmB. 7.35 gmC. 73.5 gmD. 147 gm

Potassium dichromate `(K_(2)Cr_(2)O_(7))` is an orange coloured compou

1.	Potassium dichromate `(K_(2)Cr_(2)O_(7))` is an orange coloured compound , very frequently used in laboratory as an oxidising agent as well as in a redox titration. It is generally prepared from chromite `(FeCr_(2)O_(4))` ore according to the following reactions: (1) Fusion of chromite ore with sodium carbonate in excess of air. `FeCr_(2)O_(4) + Na_(2)CO_(3) + O_(2) rarr Na_(2)CrO_(4)+Fe_(2)O_(3) +CO_(2)` (2) Acidifing filtered sodium chromate solution with sulphuric acid. `Na_(2)CrO_(4) + H_(2)SO_(4) rarr Na_(2)Cr_(2)O_(7) + Na_(2)SO_(4) + H_(2)O` (3) Treating sodium dichormate with potassium choride . `Na_(2)Cr_(2)O_(7) + KCl rarr K_(2)Cr_(2)O_(7) + NaCl` If whole of the chormite ore given in the previous question gets consumed and sufficient amount of rest of the reactants are given, then the mass of `K_(2)Cr_(2)O_(7)` obtained is:A. 14.7 gmB. 7.35 gmC. 73.5 gmD. 147 gm
Answer» Correct Answer - C

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