TS EAMCET 18-July-2022 Shift 1 Solved Paper

2‌Na(s)+2H2O(l)⟶2‌NaOH(aq)+H2(g)
1 mole of Na=23g of Na
4 moles of Na=92g of Na
2 moles of Na reacts with 2 moles of H2O to form 1 mole of H2 .
4 moles of Nawill react with 4 moles of H2O to form 2 moles of H2.
Work done by expansion of gas is given by −p∆V
p∆V=∆ngRT
At constant external pressure, ∆V=VH2−0=VH2
p∆V=∆ngRT
p∆V=∆ngRT=2×8.314×300=4.98‌kJ
Therefore, the work done is 4988.4J .
Since it is work of expansion so will be with negative sign (−4988.4J) .