Solutions Questions and Answers

The vapour pressure of pure liquid components A and B are 120 and 180 mm respectively. An ideal solution is prepared by mixing of A and B in which mole fraction of Á in vapour phase is 0.4, the V.P. of solution will be (B) 156 mm (D) 165 mm (A) 150 mm (C) 144 mm

A chemist prepares an aqueous solution of sodium hydroxide. The solution contains 12.0 g of NaOH and has a volume of 600 mL. What is the molarity of this solution? a) 0.00050 M b) 7.5 M c) 0.50 M d) 20 M

A 50.0-mL sample of a 1.35 M HCl is neutralized with NaOH solution. If 41.2 mL of NaOH are required to complete the neutralization, what is the concentration of the sodium hydroxide solution? a) 0.899 M b) 0.610 M c) 1.64 M d) 1.11 M

Calculate the vapor pressure and freezing point for a solution that contains 2.00 g of AI(NO3)3 in 15.0 g of water. K, for water is 1.86°C/m; vapor pressure of pure water at 25°C = 23.8 mmHg. (Assume complete dissociation of the solute in solution) Enter your calculated answer below and be sure to upload your work and calculations to receive full credit. (Note: Correct answers without supporting work earn 0 points)

A sample of potassium hydrogen phthalate (also known as KHP) is dissolved in 100.0 mL of deionized water and 2 drops of phenolpthalein are added to the solution. The solution is titrated with a Ca(OH)₂ solution of unknown concentration, and the following data collected.

A stock solution has a concentration of 14.5 g/L. A 3.625 g/L solution is required. If you use a 25.0 mL volumetric flask for the dilution, what volume (in mL) needs to be taken from the stock solution? Give your answer to three significant figures.

A solution of sodium hydroxide is standardized to a concentration of 0.600 M NaOH. If 20.05 mL of this NaOH solution are required to titrate 10.00 mL of an HCI solution, determine the molarity (mol/L) of the HCI solution. NaOH (aq) + HCI (aq) NaCl (aq) + H2O (l)

2.65 mL is taken from a stock solution of concentration 0.600 M and added to a 10.0 mL volumetric flask and diluted up to the calibration mark. What is the new concentration (in M)? Give your answer to three significant figures.

A solution of phosphoric acid was prepared by dissolving 10.0 g of H3PO4 in 100.0 mL of water. The resulting volume was 104 mL. Answer the next 3 questions based on this information. (Assume water has a density of 1.00 g/mL) Calculate the mole fraction of phosphoric acid in the solution above.

Calculate the mass in grams of CuSO4.5H₂O required to make up a 1.68 M aqueous solution in a 125.0 mL volumetric flask. The molar mass of CuSO4.5H₂O is 249.7 g/mol. Give your answer to three significant figures.

A chemist must prepare 500.0 mL of hydrochloric acid solution with a pH of 1.60 at 25 °C. He will do this in three steps: • Fill a 500.0 mL volumetric flask about halfway with distilled water. • Measure out a small volume of concentrated (8.0M) stock hydrochloric acid solution and add it to the flask. Fill the flask to the mark with distilled water. Calculate the volume of concentrated hydrochloric acid that the chemist must measure out in the second step. Round your answer to 2 significant digits.

Calculate the vapor pressure (in mmHg) of a solution containing 24.5 g of glycerin (C3H8O3), a non-volatile solute in 135 mL of water at 30.0°C. The vapor pressure of pure water at this temperature is 31.8 mmHg. (Density of water = 1.00 g/mL) (Enter answer without units)

Determine the pH and pOH for each of the following solutions: [OH-] = 9.5x10-9 M Express your answer using two decimal places. [OH-] = 9.5x10-9 M Express your answer using two decimal places.

Calculate the new boiling and freezing temperatures of 4451 g water when 1.01 kg of ethylene glycol (antifreeze, C₂H602) is added. enter answer with correct sig figs, no unit [NOTE: watch sig figs in mixed math!] Tbp pure water = 100.0°C Tfp pure water = 0.00 °C Kbp0.512 °C/m Kfp = 1.86 °C/m Molar mass of ethylene glycol = 62.07 g/mol

In the "decomposition of baking soda" experiment, you were asked to determine the % baking soda in an unknown mixture of salts by measuring the mass loss of H₂CO3(g). Which of the following could be a reason for why the mass loss of H₂CO3(g) was a measure of how much baking soda was in the mixture? The other salts in the mixture had much higher melting points. All of these could be viable reasons. The cool flame wasn't hot enough to decompose the other salts. Baking soda was the only salt in the mixture that contained bicarbonate.

A solution is made by mixing 34. g of acetyl bromide (CH3COBr) and 126. g of chloroform (CHCl3).

If 14.45 ml of H₂SO4(aq) is required to reach the end point when titrated with 25.00 mL of your standardized sodium hydroxide solution (use your average molarity), what is the concentration of the acid? Write the balanced chemical equation for this neutralization reaction.

You wish to prepare 140.0 mL of a 2.0 M solution of NaOH by diluting a concentrated 10.0 M NaOH solution. What volume of the concentrated solution is required to do this? a) 28 mL b) 0.47 mL c) 42 mL d) 700 mL

A chemist must prepare 225. mL of 1.00 M aqueous aluminum sulfate (Al2(SO4)3) working solution. She'll do this by pouring out some 1.21 M aqueous aluminum sulfate stock solution into a graduated cylinder and diluting it with distilled water. Calculate the volume in mL of the aluminum sulfate stock solution that the chemist should pour out. Round your answer to 3 significant digits.

The wastewater solution from a factory containing high levels of salts needs to be diluted before it can be released into the environment. Therefore, two containers of waste solution are separated by a semipermeable membrane and pressure is applied to one container, forcing only water molecules through the membrane and diluting the waste solution in the other container. As dilution continues, higher and higher pressures are needed to counteract the natural tendency for the water molecules to have a net flow back toward the more concentrated solution. What was the applied pressure at the end of this process if the final concentrations of the solutions were 0.053 M and 0.190 M at a temperature of 23 °C? Express your answer with the appropriate units.

The precipitation of aluminum hydroxide, Al(OH)3 (Ksp = 1.3 x 10-33), is sometimes used to purify water. The Ksp can be used to find the concentration of hydroxide ions, and thus determine the pH given a concentration of of aluminum. At what pH will precipitation of Al(OH)3 begin if 4.90 lb of aluminum sulfate, Al2(SO4)3, is added to 1150 gallons of water (with a negligible change in volume)? Express your answer numerically to two decimal places.

Calculate the concentration of an aqueous KCI solution if 541 mL of the solution gives 37.4 g of AgCl when treated with excess AgNO 3. The equation for the reaction is KCl(aq) + AgNO 3(aq) AgCl(s) KNO 3(aq)

Calculate the volume of 1.87 M Nal that would be needed to precipitate all of the Hg +2 ion from 199 mL of a 1.96 M Hg(NO3)2. The equation for the reaction is 2 Nal(aq) + Hg(NO3)2(aq) Hgl2( s) + 2 NaNO3(aq)

If consuming antacids and proton pump inhibitors causes stomach pH to increase from pH 2 to pH 4, the hydronium ion concentration becomes a. 20 times higher b. 100 times lower c. 20 times lower d. 2 times lower e. 2 times higher f. 100 times higher

A strong acid is one that dissociates 100% into ions, so that the hydronium ion concentration is equal to the molarity of the acid. This means that a 0.0010 M solution of the strong acid HCI would have a: a. pH = 3 b. pH = 11 c. pH = 1 d. can't be determined e. pH = 2

An aqueous potassium carbonate solution is made by dissolving 5.67 moles of K2CO3 in sufficient water so that the final volume of the solution is 2.00 L. Calculate the molarity of the K2CO3 solution.

Sodium hydroxide is extremely soluble in water. At a certain temperature, a saturated solution contains 565 g NaOH(s) per liter of solution. Calculate the molarity of this saturated NaOH(aq) solution.

An aqueous solution has a normal boiling point of 103.0°C. What is the freezing point of this solution? For water Kb = 0.51 °C/m and Kf = 1.86 °C/m. A) -0.82°C B) -3.0°C C) -3.6°C D) -11°C

The maximum contaminant level of arsenic (As) in drinking water as set by the the Environmental Protection Agency (EPA) is 0.000010 g L-¹. Express this concentration in parts per million (ppm). Assume the density of water is 1.00 g/mL.

How many milliliters of a 0.900% (m/v) normal saline solution can be prepared from 3.50 g of sodium chloride, NaCl? Note that mass is not technically the same as weight, but the abbreviation % (w/v) is often used interchangeably with % (m/v).

Calculate the percent mass per volume, % (m/v), of a dextrose solution containing 6.50 g of dextrose in 225 mL of solution. Note that mass is not technically the same as weight, but the abbreviation % (w/v) is often used interchangeably with % (m/v).

How many milliliters of 11.5 M HCl(aq) are needed to prepare 435.0 mL of 1.00 M HCl(aq)?

Calculate the mass percent of solute in each solution. Calculate the mass percent of 2.87 g KCl dissolved in 54.1 g H₂O. Calculate the mass percent of 22.1 g KNO3 dissolved in 858 g H₂O.

A substance that fully ionizes in aqueous solution is called a A. non-conductor B. non-electrolyte C. strong electrolyte D. semiconductor E. weak electrolyte