Chapter 1, Problem 1.105E

What is the difference between (a) mass and density? (b) an extensive and an intensive property? (c) a solvent and a solution?

A soft drink contains an unknown mass of citric acid, C3H5O(COOH)3. It requires 6.42 mL of 9.580 × 10−2-M NaOH to neutralize the citric acid in 10.0 mL of the soft drink. C3H5O(COOH)3(aq) + 3 NaOH(aq) → Na3C3H5O(COO)3(aq) + 3 H2O(ℓ) Determine which step in these calculations for the mass of citric acid in 1 mL soft drink is incorrect? Why? n (NaOH) = (6.42 mL)(1L/1000 mL)(9.580 × 10−2 mol/L) n (citric acid) = (6.15 × 10−4 mol NaOH) × (3 mol citric acid/1 mol NaOH) m (citric acid in sample) = (1.85 × 10−3 mol citric acid) × (192.12 g/mol citric acid) m (citric acid in 1 mL soft drink) = (0.354 g citric acid)/(10 mL soft drink) Determine the correct result.

If 14.5 kJ of heat were added to 485 g of liquid water, how much would its temperature increase?

A 15.00 g sample of a solid substance is placed in 100.0 g of water at 25°C, and all of the solid dissolves. Then another 2.00 g of the substance is added, and all of it dissolves. A final 2.00 g is added, and none of it dissolves. •Is the first solution saturated, unsaturated, or supersaturated? •Is the second solution saturated, unsaturated, or supersaturated? •What can you tell about the final solution that is in contact with the solid?

The solubility of magnesium chloride in water is 54.3 g/100 mL of water at 20 C. If you have a solution that has 195.0 g of magnesium chloride in 350 mL of water, the solution is  (saturated or unsaturated). There  (would or would not) be solid magnesium chloride on the bottom of the container.

A geochemist measures the concentration of salt dissolved in Lake Parsons and finds a concentration of 11.10 g.L-¹. The geochemist also measures the concentration of salt in several nearby non-isolated lakes, and finds an average concentration of 4.30 g⋅L¯¹. Assuming the salt concentration in Lake Parsons before it became isolated was equal to the average salt concentration in nearby non-isolated lakes, calculate the percentage of Lake Parsons which has evaporated since it became isolated. Be sure your answer has the correct number of significant digits.

A geochemist measures the concentration of salt dissolved in Lake Parsons and finds a concentration of 69.32 g.L The geochemist also measures the concentration of salt in several nearby non-isolated lakes, and finds an average concentration of 5.02 g⋅L¯¹. Assuming the salt concentration in Lake Parsons before it became isolated was equal to the average salt concentration in nearby non-isolated lakes, calculate the percentage of Lake Parsons which has evaporated since it became isolated. Be sure your answer has the correct number of significant digits.

An aqueous solution of sodium chloride,NaCl , is made by dissolving 1.01 grams of sodium chloride in sufficient water in a 50.0 mL volumetric flask, and then adding enough water to fill the flask to the mark. What is the weight/volume percentage of sodium chloride in the solution? Weight/volume percentage =           %

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