Inorganic questions--please show work and only answer if you truly understand it
ID: 502330 • Letter: I
Question
Inorganic questions--please show work and only answer if you truly understand it:
Please show all work and answers on this page if at all possible.
5. Arrange the following solutions in order of decreasing freezing point, and explain your reasoning: 0.50 m HCl, 0.50 m glucose, 0.50 m acetic acid.
6. The alcohol content of hard liquor is normally given in terms of the “proof”, which is defined as twice the percentage by volume of ethanol (C2H5OH) present. Calculate the number of grams of alcohol present in a glass of of 75-proof gin (assume a 4 oz glass). The density of ethanol is 0.798 g/mL.
7. You find a solution on the shelf that is labeled 30% NH3 (aq). The density of the solution is 0.982 g/mL. Calculate the following:
a) mole fraction of ammonia = ____________
b) molality of ammonia = ____________
c) molarity of ammonia = ____________
8. Adrenaline is the hormone that triggers release of extra glucose molecules in times of stress or emergency. A solution of 0.64 g of adrenaline in 36.0 g of CCl4 causes an elevation of 0.49C in the boiling point. Given that the kb for CCl4 is 5.02 C/m, what is the molecular mass of adrenaline.
9. The Henry's Law constant for the solubility of nitrogen in water is 6.40x10-4 M/atm at 25.0 Celsius. At 570 torr, how many grams of N2 can be dissolved in 250 L of water at 25.0 degrees Celsius
10. What is the osmotic pressure of a 1.36 M aqueous solution of urea [(NH2)2CO)] at 22.0C ?
Explanation / Answer
5) The freezing point will be depressed most by the solution that contains the most
solute particles.
Classify each solute as a strong electrolyte, a weak electrolyte, or a
nonelectrolyte.
Here, three solutions have the same concentration (0.50m), so comparing the solutions is straight forward.
HCl is a strong electrolyte, so under ideal conditions it will
completely dissociate into two particles per molecule.
HCl. ------> H+ + Cl-
Acetic acid is a weak electrolyte, so it will only dissociate to a small extent.
CH3COOH <-----> CH3COO- + H+
Glucose is a nonelectrolyte, so glucose molecules remain as glucose molecules in solution.
for these solutions, the order in which the
freezing points become lower is:
0.50 m glucose > 0.50 m acetic acid > 0.50 m HCl
The HCl solution will have the lowest freezing point