1. For the following processes, state whether the heat (g), work (w), and change in internal energy (AU) is greater than, equal to, or less than zero for the specified system, and explain a) An ideal gas expands isothermally against an external pressure of 1 atm. b) A reversible, adiabatic expansion of an ideal gas. c) An ideal gas expands adiabatically into a vacuum. d) Water vapor at 100 C and 1 atm pressure (boiling point) is compressed at slightly higher pressure and changes phase into liquid water (tricky, think about the energy of the phase change,

You weighed your empty insulated cup and found that the mass of the cup was 3.6 g.  You add some hot water and find that the total mass increases to 26.3 g.  You got some ice from the bus tub, and found that it was wet.  After drying it carefully, you take the temperature of the hot water in the cup and find that its temperature is 55.9 °C and then add the ice.  The temperature of the water dropped, and came to equilibrium at 35.2 °C.  At the end of the experiment you re-weigh the cup and find that the mass has increased to 31.7 g. What is your experimental value for the heat of fusion?

Calculate the enthalpy change when a 2.841 g sample is burned in excess oxygen to form co2 and h20 in a reaction at constant pressure and 298k  use the following information: co2=-393.51Kj h20=-285.83Kj o2= 0 Kj C6h6= 49.03 Kj

ences to access important values if needed for this question. When 5.42 g of potassium bromide (KBr) is dissolved in 114g of water in a styrofoam calorimeter of negligible heat capacity, the temperature drops from 25.00 to 23.03 °C. Based on this observation, calculate q for the water and AH° for the process, assuming that the heat absorbed by the salt is negligible, KBr(s) K*(aq) + Br (aq) The specific heat of water is 4.184] °C¹g¹. Give the answers in kJ. ан, о AHO