Question

Potassium dichromate when heated with concentrated sulphuric acid and a soluble chloride, gives brown-red vapours of :

• A. $CrO_3$
• B. $CrCl_3$
• C. $CrO_2Cl_2$
• D. $Cr_2O_3$

Answer 1

Answer: (C)

$CrO_2Cl_2$

Answer 2

Solid potassium dichromate when heated with concentrated sulphuric acid and a soluble chloride gives orange red vapours of a volatile oily liquid $CrO_2Cl_2$ $K_{2}Cr_{2}O_{7}+4NaCl+6H_{2}SO_{4}\,\to 2KHSO_{4}+4NaHSO_{4}+2CrO_{2}Cl_{2}$ chromyl chloride