Question

Determine the amount of heat required to convert 500.0 g of liquid ethanol at 25.0°C into gaseous ethanol at 125°C. Use the following information on ethanol (C2H5OH) to calculate the amount of heat for each of the steps. Melting Point = −117°C Boiling Point = 78.3°C Molar Heat Capacities: Csolid =113 J/mol °C Cliquid = 420 J/mol °C ΔHfusion = 5.02 kJ/molΔHvaporization = 39.3 kJ/mol

Answer 1

The amount of heat required for each step is calculated as follows: Q q1+2+93 where, (IpMou) - (ma) mc dT lig mAH vp 92 (mcdT 1ap (Ih u) Where, m is the mass of the ethanol 500 g Calculating g as follows h-(ncdr lig where Cli =113 J/mol °C 500g = 10.85 mol m = 46.07g/mol dT Toiin-Tnitial _ 78.3C-(25.0°c) 53.3°C Therefore, (10.85molx113 J /mol °Cx53.3°C) 65.348k

To calculate q, as follows: (nAH. 92 39.3 kJ/ mol ДН. 1ap n 10.85 mol q, 10.85 mol x 39.3 kJ/ mol - 426.405 kJ as follows: Calculating q ncdT 9з vap n 10.85mol = C 420 J/mol°C _ dT 125°C 78.3°C -46.7°C 3 10.85mol x 420 J/ moloCx 46.7°C 212.811 kJ Therefore, Q +2+3 -65.348 kJ +426.405 kJ+212.811kJ 704.564 kJ