<p>A mixture of 2.3g formic acid and 4.5g oxalic acid is treated with conc.&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>H</mi><mn>2</mn></msub><mi>S</mi><msub><mi>O</mi><mn>4</mn></msub></math>. The evolved gaseous mixture is passed through KOH pellets. Weight (in g) of the remaining product at STP will be:</p>