Question

7.44 Classify each of the following as a solution, a colloid, or a suspension. a. Soft drink b. Cream c. Muddy Water d. Bleach 7.48 A dextrose solution contains 40. mEq/L Na+ and 15 mEq/L of HPO42‐, in addition to other ions. How many milliequivalents of each ion are present in 320 mL? 7.52 If the solubility of sucrose in 100 mL of H2O is 204 g at 20oC and 260 g at 50oC, label each of the following solutions as unsaturated, saturated, or supersaturated. If more solid is added than can dissolve in the solvent, assume that undissolved solid remains at the bottom of the flask a. Adding200gto100mLofH2Oat20oC b. Adding110gto50mLofH2Oat20oC c. Adding 220 g to 100 mL of H2O at 50oC and slowly cooling to 20oC to give a clear solution with no precipitate 7.54 Which compounds are soluble in water? a. C5H12 b. CaCl2 c. CH3Br 7.60 Which of the following pairs of compounds form a solution? a. KCl and CCl4 b. 1‐propanol (C3H8O) and H2O c. pentane (C5H12) and hexane (C6H14) 7.64 What is the weight/volume percent concentration using the given amount of solute and total volume of solution? a. 5.5 g LiCl in 550 mL of solution b. 12.5 g NaNO3 in 250 mL of solution c. 20.0 g of NaOH in 400. mL of solution 7.68 What is the molarity of a solution prepared using the given amount of solute and total volume of solution? a. 2.4 mol of NaOH in 1.50 L of solution b. 0.48 mol of KNO3 in 750 mL of solution c. 25.0 g of KCl in 650 mL of solution 7.72 How many moles of solute are contained in each solution? a. 250 mL of a 0.55 M NaNO3 solution b. 145 mL of a 4.0 M HNO3 solution c. 6.5Lofa2.5MHClsolution 7.80 The maximum safe level of each metal in drinking water is given below. Convert each value to parts per million. a. copper, 1300 g/kg b. arsenic, 10 g/kg c. chromium, 100 g/kg 7.86 How many milliliters of 5.0 M sucrose would be needed to prepare each solution? a. 45mLofa4.0Msolution b. 150mLofa0.5Msolution c. 1.2Lofa0.025Msolution

Answer 1

answer.Q.7.44 soft drink--colloidal solution

cream -----colloidal solution

muddy water----suspension

bleach ------colloidal solution.

Q.7.86 given M1=5.0 M (a) M2=4.0M,V2=45 ml then M1V1=M2V2

5xV1=4x45 ==>V1=36 ml.

36 ml of 5M sucrose solution is enough to prepare 45 ml of 4 M solution.

   (b) M2=0.5M,V2=150 ml 5xV1=0.5x150 ==>V1=15 ml.

15ml of 5M sucrose solution is enough to prepare 150 ml of 0.5 M solution.

(c) M2=0.025 V2=1200 ml 5xV1=1200x0.025

V1=2.5x12/5=6 ml

V1=6ml

6 ml of 5M sucrose solution is enough to prepare 1.2L of 0.025M solution.