D-And F-Block Elements Ques 495
Question: Potassium dichromate when heated with concentrated sulphuric acid and a soluble chloride, gives brown-red vapours of:
Options:
A) $ CrO_3 $
B) $ CrCl_3 $
C) $ CrO_2Cl_2 $
D) $ Cr_2O_3 $
Show Answer
Answer:
Correct Answer: C
Solution:
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_2Cr_2O_7+4NaCl+6H_2SO_4 $ $ \underset{chromylchloride}{\mathop{\xrightarrow{{}}2KHSO_4}},+4NaHSO_4+2CrO_2Cl_2 $
