Use the value of enthalpy you determined for CaCl2 to calculate what quantity of salt will be needed to make a chemical hot pack. Assume using 100 g (100 mL) of water and changing the temperature from 25 °C to 60 °C. Show all calculations. avg. mol enthalpy of solution: -4.6kJ/mol

18 Suppose you had a mixture containing 8.0 moles of isopropanol (C3H7OH) and 15.0 moles of water (H₂O) at 40.0°C. The vapor pressure of pure isopropanol at this temperature is 100.0 torr while that of water is 55.36. torr. XA B. U What is the mole fraction of isopropanol and water in the solution? NA nT = 8.0 23.0 X isopropanol = X water = Find the partial pressures of isopropanol and water in the solution. Pisopropanol = P water= 0.3 Find the mole fraction of isopropanol and water above the solution X isopropano = X water =

A pharmacist mixes togehter 20 g of crystals of compound A and 10g of crystals of compound B. The mixture is then dissolved in 120mL of water to make cough syrup.

Phenanthrene, C14H10, is an aromatic hydrocarbon. Some phenanthrene is dissolved in 50.0 g of benzene and the boiling point of the resulting solution is 80.51°C. What mass of phenanthrene must have been dissolved? The Kb for benzene is 2.53 °C/m and the boiling point of pure benzene is 80.2°C.