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Chapter 13.1-13.4 problems. November 28, 2011. What IMF(s) is/are present when… a) KCl is dissolved in H 2 O b) carnauba wax dissolves in castor oil c) Methanol (CH 3 OH) vs CCl 4. Arrange the following in increasing solubility: A B C.
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Chapter 13.1-13.4 problems November 28, 2011
What IMF(s) is/are present when… a) KCl is dissolved in H2Ob) carnauba wax dissolves in castor oil c) Methanol (CH3OH) vs CCl4
Which solvent will yield the highest concentration of NaCl? a) b)
Which will have the highest concentration in diethyl ether ( ) ? A. HCl (g) B. NaCl (s) C. H2O
Why will washing your face with soap make your face “dryer”? (clue: remember your lipbalm experiment)
When NH4Cl dissolves in water, the solution becomes colder… • Is ΔHsol’n >, < or = to 0? • Is ΔHlattice >, <, or = to ΔHhydration ? • Is the dissolution mostly due to ΔH or ΔS of mixing?
CHARGE DENSITY affects ΔHhydration. Which one will have a higher (more negative) ΔHhydration? • Na+ , Rb+ • Br-, I- • Ca2+, Na+
Which one best describes the enthalpy diagram of dissolving KBr in hexane?
Henry’s Law constant (kH) of O2 in water at 20oC is 1.28 x 10-3 mol/L-atm. • How many grams will dissolve in 2.50 L H2O that is in contact with pure O2 at 1.00 atm? • How many grams will dissolve in 2.50 L H2O that is in contact with pure O2 at 0.209 atm?
Express the concentration of concentrated HCl (12M)? Assume density of solution to be that of water: 1.00g/mL • Molality • %w/w • %v/v • Mol fraction
Argon makes up 0.93% by volume of air. Calculate its solubility (in molars) in water at 20oC and 1.0 atm. (kH of Ar is 1.5x10-3 mol/L-atm)
How many grams of NaCl more is needed to prepare a 100.0 mL of 0.1000 molal from 100.0 mL of 0.1000 molar NaCl solution?
How many grams of water must be evaporated from a liter of solution to make a 20%(w/w) MgBr2 to make a 0.0010 molar solution?
You are to prepare 10.0mL 0.0430 M ethanol solution from a stock solution of 20% v/v ethanol. The density of ethanol is 0.789g/mL. How many mL of the stock solution should you use?
Air is 21%(w/w) oxygen. If the molar mass of air is 28.4 grams/mol, calculate the mol ratio of oxygen in the air.