Chapter 16, Problem 132E

Interpretation Introduction

(a)

Interpretation:

Whether the statement, “The concentration is the same throughout a beaker of the solution” is true or false is to be stated.

Concept introduction:

The solution is defined as the mixture of two or more substances where the substances in a relative amount get chemically combined that is, they get mixed together, homogenously. The amount of the substances mixed can be varied according to the limit of solubility.

Answer to Problem 132E

The statement, “The concentration is the same throughout a beaker of the solution” is true.

Explanation of Solution

The solution forms a homogenous mixture of solute and solvent. So, the concentration is same throughout the solution. Therefore, the statement, “The concentration is the same throughout a beaker of the solution” is true.

Conclusion

The statement, “The concentration is the same throughout a beaker of the solution” is true.

Interpretation Introduction

(b)

Interpretation:

Whether the statement, “A saturated solution of solute A is always more concentrated than an unsaturated solution of solute B” is true or false is to be stated.

Concept introduction:

When the maximum amount of solute is dissolved in a solvent then it is known as a saturated solution. The unsaturated solution is one in which less amount of solute is added to the solvent.

Answer to Problem 132E

The statement, “A saturated solution of solute A is always more concentrated than an unsaturated solution of solute B” is false.

Explanation of Solution

The comparison of concentration between the two solutions can be done when the solute particles of both the solutions are same. In this case the solute particles are different for both the solutions.

Therefore, the statement, “A saturated solution of solute A is always more concentrated than an unsaturated solution of solute B” is false.

Conclusion

The statement, “A saturated solution of solute A is always more concentrated than an unsaturated solution of solute B” is false.

Interpretation Introduction

(c)

Interpretation:

Whether the statement, “A solution can never have a concentration greater than its solubility at a given temperature” is true or false is to be stated.

Concept introduction:

The solution is defined as the mixture of two or more substances where the substances in a relative amount get chemically combined that is, they get mixed together, homogenously. The amount of the substances mixed can be varied according to the limit of solubility. The concentration of solution is defined as the amount of solute particles added to the amount of solvent or solution.

Answer to Problem 132E

The statement, “A solution can never have a concentration greater than its solubility at a given temperature” is false.

Explanation of Solution

In a supersaturated solution, more amount of solute is added after the saturation limit by altering its temperature conditions. So, the concentration will be more than the solubility.

Therefore, the statement, “A solution can never have a concentration greater than its solubility at a given temperature” is false.

Conclusion

The statement, “A solution can never have a concentration greater than its solubility at a given temperature” is false.

Interpretation Introduction

(d)

Interpretation:

Whether the statement, “A finely divided solute dissolves faster because more surface area is exposed to the solvent” is true or false is to be stated.

Concept introduction:

When the solute and the solvent are mixed together then they form a solution. The solute is the matter that gets dissolved in the solvent. The concentration of solution is defined as the amount of solute particles added to the amount of solvent or solution.

Answer to Problem 132E

The statement, “A finely divided solute dissolves faster because more surface area is exposed to the solvent” is true.

Explanation of Solution

The solubility of a solute in a solvent is directly proportional to the surface area of the solute particles. A finely divided solute has more surface area.

Therefore, the statement, “A finely divided solute dissolves faster because more surface area is exposed to the solvent” is true.

Conclusion

The statement, “A finely divided solute dissolves faster because more surface area is exposed to the solvent” is true.

Interpretation Introduction

(e)

Interpretation:

Whether the statement, “Stirring a solution increases the rate of crystallization” is true or false is to be stated.

Concept introduction:

The solution is defined as the mixture of two or more substances where the substances in a relative amount get chemically combined that is, they get mixed together, homogenously. The amount of the substances mixed can be varied according to the limit of solubility.

Answer to Problem 132E

The statement, “Stirring a solution increases the rate of crystallization” is false.

Explanation of Solution

Stirring a solution increases the solubility of the solute particles as it increases the motion of the solute particles in the solvent.

Therefore, the statement, “Stirring a solution increases the rate of crystallization” is false.

Conclusion

The statement, “Stirring a solution increases the rate of crystallization” is false.

Interpretation Introduction

(f)

Interpretation:

Whether the statement, “Crystallization ceases when equilibrium is reached” is true or false is to be stated.

Concept introduction:

The solution is defined as the mixture of two or more substances where the substances in a relative amount get chemically combined that is, they get mixed together, homogenously.

Crystallization is a process in which the change in state of materials occurs from liquid to solid.

Answer to Problem 132E

The statement, “Crystallization ceases when equilibrium is reached” is false.

Explanation of Solution

Equilibrium is a state of balance between the rate of dissolution and the rate of crystallization. Therefore, both the dissolution and crystallization occurs at a same rate.

Therefore, the statement, “Crystallization ceases when equilibrium is reached” is false.

Conclusion

The statement, “Crystallization ceases when equilibrium is reached” is false.

Interpretation Introduction

(g)

Interpretation:

Whether the statement, “All solubilities increase at higher temperatures” is true or false is to be stated.

Concept introduction:

The solution is defined as the mixture of two or more substances where the substances in a relative amount get chemically combined that is, they get mixed together, homogenously. The amount of the substances mixed can be varied according to the limit of solubility.

Answer to Problem 132E

The statement, “All solubilities increase at higher temperatures” is false.

Explanation of Solution

The solubilities depend on the nature of solute particles.

When the solute particle is solid, then the solubility increases with increase in temperature. On the other hand, when the solute particle is gaseous, then the solubility decreases with increase in temperature.

Therefore, the statement, “All solubilities increase at higher temperatures” is false.

Conclusion

The statement, “All solubilities increase at higher temperatures” is false.

Interpretation Introduction

(h)

Interpretation:

Whether the statement, “Increasing air pressure over water increases the solubility of nitrogen in the water” is true or false is to be stated.

Concept introduction:

The solution is defined as the mixture of two or more substances where the substances in a relative amount get chemically combined that is, they gets mixed together, homogenously. The amount of the substances mixed can be varied according to the limit of solubility.

Answer to Problem 132E

The statement, “Increasing air pressure over water increases the solubility of nitrogen in the water” is true.

Explanation of Solution

When the solute particle is in a gaseous state, then the solubility of the solute particle can be increased by increasing the pressure on the water. In this case, the solute is nitrogen gas, so its solubility can be increased by increasing the pressure on it.

Therefore, the statement, “Increasing air pressure over water increases the solubility of nitrogen in the water” is true.

Conclusion

The statement, “Increasing air pressure over water increases the solubility of nitrogen in the water” is true.

Interpretation Introduction

(i)

Interpretation:

Whether the statement, “An ionic solute is more likely to dissolve in a nonpolar solvent than in a polar solvent” is true or false is to be stated.

Concept introduction:

The solution is defined as the mixture of two or more substances where the substances in a relative amount get chemically combined that is, they get mixed together, homogenously.

When the compounds get dissociated into ions on dissolution dissolved in water, then they are known as ionic compounds.

Answer to Problem 132E

The statement, “An ionic solute is more likely to dissolve in a nonpolar solvent than in a polar solvent” is false.

Explanation of Solution

Polar solutes dissolve in polar solvents and nonpolar solutes dissolve in nonpolar solvents.

Ionic solute is polar in nature, so, it will dissolve in polar solvent much easily than the nonpolar solvent.

Therefore, the statement, “An ionic solute is more likely to dissolve in a nonpolar solvent than in a polar solvent” is false.

Conclusion

The statement, “An ionic solute is more likely to dissolve in a nonpolar solvent than in a polar solvent” is false.

Interpretation Introduction

(j)

Interpretation:

Whether the statement, “The molarity of a solution changes slightly with temperature, but the molality does not” is true or false is to be stated.

Concept introduction:

Molality is defined as the number of moles of solute present in the specific weight of solvent in kilograms.

Molarity is defined as the number of moles of solute present in specific volume of solution in liters.

Answer to Problem 132E

The statement, “The molarity of a solution changes slightly with temperature, but the molality does not” is true.

Explanation of Solution

Molarity is defined as the number of moles of solute present in specific volume of solution in liters. The volume of a solution is temperature dependent, so it changes with temperature. On the other hand, molality is the number of moles of solute present in the specific weight of solvent in kilograms. The mass of solvent is not temperature dependent, so it does not change with temperature.

Therefore, the statement, “The molarity of a solution changes slightly with temperature, but the molality does not” is true.

Conclusion

The statement, “The molarity of a solution changes slightly with temperature, but the molality does not” is true.

Interpretation Introduction

(k)

Interpretation:

Whether the statement, “If an acid and a base react on a $2:1$ mole ratio, there are twice as many equivalents of acid as there are of base in the reaction” is true or false is to be stated.

Concept introduction:

The quantity of a substance having same number of atoms, ions, or molecules as the number of atoms in $\text{12}\text{g}$ of $\text{carbon-12}$ is defined as a mole. The number of equivalents of an acid and base are equal in a neutralization reaction.

Answer to Problem 132E

The statement, “If an acid and a base react on a $2:1$ mole ratio, there are twice as many equivalents of acid as there are of base in the reaction” is false.

Explanation of Solution

The number of equivalents of an acid and base are equal but the number of equivalents of acid per mole is not equal to the numberof equivalents of a base per mole.

When an acid and a base reacts in a $2:1$ mole ratio, then the number of equivalents of acid per mole is $1$ and the number of equivalents of base per mole is $2$.

Therefore, the statement, “If an acid and a base react on a $2:1$ mole ratio, there are twice as many equivalents of acid as there are of base in the reaction” is false.

Conclusion

The statement, “If an acid and a base react on a $2:1$ mole ratio, there are twice as many equivalents of acid as there are of base in the reaction” is false.

Interpretation Introduction

(l)

Interpretation:

Whether the statement, “The concentration of a primary standard is found by titration” is true or false is to be stated.

Concept introduction:

The solution is defined as the mixture of two or more substances where the substances in a relative amount get chemically combined that is, they get mixed together, homogenously.

The concentration of solution is defined as the amount of solute particles added to the amount of solvent or solution.

Answer to Problem 132E

The statement, “The concentration of a primary standard is found by titration” is false.

Explanation of Solution

The primary standard is obtained by accurately weighing the solid substance and not by titration.

Therefore, the statement, “The concentration of a primary standard is found by titration” is false.

Conclusion

The statement, “The concentration of a primary standard is found by titration” is false.

Interpretation Introduction

(m)

Interpretation:

Whether the statement, “Colligative properties of a solution are independent of the kinds of solute particles, but they are dependent on particle concentration” is true or false is to be stated.

Concept introduction:

Colligative properties are the properties which depend on the number of solutes.

It is defined as the physical property of some dilute solutions which depend on the molal concentration of the solutes.

Answer to Problem 132E

The statement, “Colligative properties of a solution are independent of the kinds of solute particles, but they are dependent on particle concentration” is true.

Explanation of Solution

The colligative properties are directly proportional to the concentration of the solute particles, and not to the nature of the solute particles.

Therefore, the statement, “Colligative properties of a solution are independent of the kinds of solute particles, but they are dependent on particle concentration” is true.

Conclusion

The statement, “Colligative properties of a solution are independent of the kinds of solute particles, but they are dependent on particle concentration” is true.