J of energy are added to a sample of gallium initially at 250 C the temperature

# J of energy are added to a sample of gallium

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23. 168.00 J of energy are added to a sample of gallium initially at 25.0 °C, the temperature rises to 38.0 °C. What is the volume of the sample?Data for Gallium, Gaspecific heat0.372 J g¯1°C¯1density5.904 g cm¯3 24.Data for Ethanol, C2H5OHmolar heat of vaporization39.3 kJ mol¯1boiling point78.3 °CUse these data to calculate ΔS for the vaporization of one moleof ethanol.(A) 0.502 kJ mol¯1°C¯1(B) 1.99 kJ mol¯1°C¯1(C) 112 J mol¯11(D) 502 J mol¯1°C¯125. The combustion of ammonia is represented by this equation.4 NH3(g) + 5 O2(g) ---> 4 NO(g) + 6 H2O (g) ΔH=- 905 kJEnthalpy of formation dataNO2(g)90.4 kJ mol¯1H2O(g)- 241 kJ mol¯1What is the enthalpy of formation for NH3(g)?(A) - 499 kJ mol¯1(B) - 46.1 kJ mol¯1(C) 184 kJ mol¯1(D) 277 kJ mol¯1 26. For which reaction is ΔH most nearly equal to ΔE?
(A) C(s) + O2(g) ---> CO2(g)(B) N2(g) + 2 O2(g) ---> 2 NO2(g)(C) 2 H2O2(l) ---> 2 H2O(l) + O2(g)(D) C2H4(g) + 3 O2(g) ---> 2 CO2(g) + 2 H2O(l) 27. For the reaction,4 NH3(g) + 5 O2(g) ---> 4 NO(g) + 6 H2O(g)which relationship is true? 28. These data were obtained in the study of the reaction between pyridine (C5H5N) and methyl iodide (CH3I)Initial Concentrations, MC5H5NCH3IInitial Rate, M s¯1Exp. 11.0 x 10¯41.0 x 10¯47.5 x 10¯7Exp. 22.0 x 10¯42.0 x 10¯43.0 x 10¯6Exp. 32.0 x 10¯44.0 x 10¯46.0 x 10¯6based on these data , what is the experimental rate law? 29. The half-life for the first-order conversion of cyclobutane to ethylene,C4H8(g) ---> 2 C2H4(g)is 22.7 at a particular temperature. How many seconds are needed for the partial pressure of cyclobutane to decrease from100mmHg to 10 mmHg? (A) 52.0 s(B) 75.4 s(C) 90.0 s(D) 227 s 30. The activation energy for a particular reaction is 83.1 kJ mol¯1. By what factor will the rate constant increase when the temperature is increased from 50.0 °C to 60.0 °C? 31. What will be the effect of increasing the temperature of reactants which are known to undergo an endothermic reaction? The effect will be to

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