A gas in the initial state of p1 = 75 psia and V1 = 5 ft.° undergoes a process to p2 = 25 psia and V2 = 9.68 ft.º, during which the enthalpy decreases 62 BTU. The ecific heat at constant volume is c, = 0.754 BTU/lb.°R. Determine (a) the change of internal energy, (b) the specific heat at constant pressure, (c) the gas constan

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The combustion of 0.150g of ethanol, CHOH(1) 2 5 releases 4.47kJ of heat. The molar enthalpy of combustion of liquid is?

The internal pressure of a gas, π = au dv)T' is a measure of intermolecular forces, because it indicates a change in internal energy as the molecules get closer or further apart, without temperature changing. = a Calculate the change in internal 1 Vm T energy, AU, when 1.5 mols of acetone (a = 16 l² atm/mo1²), expands from 2 liters to 5 liters at a constant temperature. ii) Would this change in internal energy be greater or smaller for an ideal gas? Why? i) Using the van der Waals equation of state, T = au

81.6 g of a metal alloy was heated to 93 o C, then plunged into 105 mL of H 2O that was at 19.5 o C. The system equilibrated at 22.3 oC. What is the specific heat of the metal?

The standard heat of formation, AH;, is defined as the enthalpy change for the formation of one mole of Part B substance from its constituent elements in their standard states. Thus, elements in their standard states have AH: = 0. Heat of formation values can be used The combustion of ethene, C2H4, occurs via the reaction to calculate the enthalpy change of any reaction. C2H4 (g) + 302 (g)→2CO2(g) + 2H20(g) Consider, for example, the reaction with heat of formation values given by the following table: 2NΟ (5) + Ο, (s) 2ΝO, (g) ΔΗρ (kJ/mol) Substance with heat of formation values given by the following table: C2H4 (g) 52.47 CO2 (g) -393.5 Substance (kJ/mol) H2O(g) -241.8 NO(g) 90.2 Calculate the enthalpy for the combustion of ethene. 02 (g) Express your answer to four significant figures and include the appropriate units. NO2(g) 33.2 • View Available Hint(s) Then the heat of formation for the overall reaction is ΔΗ ΔΗ (products) -ΔΗ; (reactants ) [2(90.2) + 0] HA ? 2(33.2) -114 kJ/mol…

3. The enthalpy change of a reaction Hrxn equals heat q, if the reaction is performed ... (A) in a closed system (B) in an isolated system (C) at constant volume (D) at constant temperature (E) at constant pressure