1) Predict whether each of these substance would be more soluble in water (polar solvent) or benzene (nonpolar solvent)
Olive oil (non polar)
Ethanol or grain alcohol ( polar)
Table Salt or NaCl (ionic)
Sugar (Polar covalent)
2) Compare the processes that occur when potassium chloride, barium hydroxide and hydrobromic acid (HBr) dissolve in water. Write out the equation and make a sketch of what is happening.
3) What is the expected conductivity of electricity of each of these substances?
Acetic acid (Vinegar)
4) At standard pressure (1 atm) and 0°C, diatomic oxygen (O2) can dissolve in water at a rate of 0.70 g/ 1 L of water. At the same temperature, but at a new pressure of 0.25 atm, how much oxygen can dissolve in water?
5) Calculate mole fraction for each of these solutes and solvents:
120 g of NH4NO3 in 300 g of water
25g of Br2 in 150 g of ethanol, C2H5OH
25g of NaCl in dichloromethane, CH2Cl2
Methanol, Ethanol and water in a solution that is 35% methanol, 40% Ethanol and 15% water
6) Practice calculating molarity:
875 g of H2SO4 in 2kg of water
Cyanic acid (HCN) in a solution that is 74% HCN by mass
A 26% solution (mass) of potassium carbonate (K2CO3) with a density of 1.09 g/cm3.
7) Predict which compound would depress freezing point the most, and explain why:
8) If a solution of MgBr2 in water freezes at -1.28°C, what is the boiling point of the solution?. Assume ideal solution behavior.
9) Explain two major differences between colloids and solutions.
10) How would you prepare a 4.5 m aqueous solution of glycerol (C3H8O3)? Calculate freezing point for this solution. This is often used by scientists to freeze bacteria- why might this molecule be a good choice?