99 Percentile Qs Bank for JEE MainChemistryThermodynamics (C)
If 92   g   Na reacts with water in open vessel at 300   K . What is the value of work done? [Assume ideal nature of the gaseous product]
Options
- A0 . 0
- B- 4988 . 4   J
- C- 2494 . 2   J
- D- 9976 . 8   J
Correct answer
B. - 4988 . 4   J
Step-by-step solution
Reaction of sodium with water will be 2 Na ( s )   +   2   H 2 O ( l )   →   2 NaOH ( aq )   +   H 2 ( g ) According to the given reaction 46 g of Na gives one mole of hydrogen gas. So, 92 g of Na will give = 92 46   =   2   moles   of   H 2   gas This is the only gaseous product so, due to this volume will increase at constant pressure. Work done at constant pressure and temperature w = - P ∆ V   =   - ∆ n g RT since produ