NACL+{{H}_{2}}S{{O}_{4}}+{{K}_{2}}C{{r}_{2}}{{O}_{7}}\,\to \]\[\UNDERSET{\text{Chromyl chloride}}{\mathop{CR{{O}_{2}}C{{l}_{2}}+}}\,{{K}_{2}}S{{O}_{4}}+N{{a}_{2}}S{{O}_{4}}\]