van der Waal's equation can be written in terms of moles per volume as n/V=((p+an^2/V^2)/RT)(1-bn/V) The van der Waal's parameters for hydrogen sulphide gas (H2S) are a = 0.448 J m3 /mol2 and b = 4.29x10^(-5) m3 /mol. Determine an estimate of the number of moles per volume of H2 S gas at 127°C and a pressure of 9.80x10^5 Pa as follows: (a) Calculate as a first approximation using the ideal gas equation, n/V=p/RT (b) Substitute this first approximation into the right-hand side of the equation derived in part (a) to find a new approximation of n/V (on the left-hand side) that takes into account real gas effects.
Solution:

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