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Chemistry - PYQ 2024

 Q. NaCl reacts with conc. H2SO4 and K2Cr2O7 to give reddish fumes (B), which react with NaOH to give yellow solution (C). (B) and (C) respectively are;

                                                        (JEE mains 2024)

1. CrO2Cl2, Na2CrO4


2. Na2CrO4, CrO2Cl2


3. CrO2Cl2, KHSO4


4. CrO2Cl2, Na2Cr2O7

NaCl + conc. H2SO4 + K2Cr2O7 →CrO2Cl2 + KHSO4 + NaHSO4 +H2O (B) Reddish brown 

CrO2Cl2 + NaOH → Na2CrO4 + NaCl +H₂O                          (C) Yellow colour

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