The compound usually added to chloroform to retard the effect of oxidation is?? And plz give one example of it showing this fact

Dear student,

Chloroform on oxidation forms a poisonous gas called phosgene by following reaction.
$2 CHC{l}_3 + O_2 \to 2COC{l}_2 + HCl$
This can be avoided by the addition of ethanol with reacts with the formed phosgene and decreases the toxicity.
$COCC{l}_2 + 2 C_2{H}_{5}OH \to CO=C{(OC}_{}$₂H₅)2 + 2 HCl

Regards