Question

Use the table below to answer the questions that follow. Thermodynamic Quantities for Selected Substances at 298.15 K (25 °C) Substance AHºf (kJ/mol) AG°f (kJ/mol) S (J/K-mol) Sulfur S (s, rhombic) 0 0 31.88 SO2(g) -269.9 -300.4 248.5 SO3(g) -395.2 -370.4 256.2 The value of AHº for the decomposition of gaseous sulfur trioxide to its component elements, 2503 (g) - 25 (s, rhombic) + 302 (8) is_1 kJ/mol O -790.4 +790.4 +395.2 0 -395.2

Answer 1

Sol! - +395.2 x 7option e) is correct Explanation A Ho (standard Enthalpy of Formation): - The standard enthalpy change for the formation of a mode of a compound from its element in their most stable states of aggregation (also known as reference states) is called Standard molar enthalpy of formation, It a symbol is Agho, where the substrept "f of compound in question has been formed in its standard State from its element in their most stable states of aggregation. Reference state: at 256 & 1 atm on Abar y indicates that that one mole - gas s-Schombic solid c- Coraphite. (solid) eg! to calculate the heat required to decomposetion of sos) The following genezal equations can be used for the enthalpy es cs, shombic) change Calculation + 30 OS 25°38) Now DH is for a mole only t 503 . aopf Afth Products] {ş bi AgHo Creactants Ss, Chombic) soft (şai :: Shiro - [*0 [ls, ]+ Ajith many] - [ suo contentory [180+% (o)]-[-395.250] products reactant = = 0+395.2 DHO = +395.2 215/mol

Method (2) - Give at 39512105/mol Soo) SO39) + Sis, shombic) 30mg) .-39502 lemon is g,g) i for decomposition Sesshombic) 39) + 3/ng) sha + 395.2 Wilmal Just reveyse the value, because here sfq are already in standard Stanke, hence it reaction is reversed magnatude is not changed, but sign Changes.