Chapter 4, Problem 21E

(a)

Interpretation Introduction

Interpretation: The preparation of $\text{2}\text{.00}\text{L}$ of $0.250\text{M}\text{NaOH}$ solution from solid $\text{NaOH}$ is to be described.

Concept introduction: Preparation of particular solution of desired concentration and volume requires certain solute’s mass. This solute’s mass is evaluated by first calculating moles. The solution’s concentration and volume when multiplied results in solute’s moles. This calculated solute’s mass is added to water to obtain the required solution.

(b)

Interpretation Introduction

Interpretation: The preparation of $\text{2}\text{.00}\text{L}$ of $0.250\text{M}\text{NaOH}$ solution from $\text{1}\text{.0}\text{M}\text{NaOH}$ stock solution is to be described.

Concept introduction: The solution possessing greater solute’s concentration is concentrated and the one possessing lower solute’s concentration is dilute. The process of making a dilute solution starting from concentration is referred as dilution. This dilution process is generally done by increasing the solvent’s amount in the solution.

(c)

Interpretation Introduction

Interpretation: The preparation of $\text{2}\text{.00}\text{L}$ of $0.100\text{M}{\text{K}}_{\text{2}}{\text{Cr}}_{\text{2}}{\text{O}}_{\text{7}}$ solution from solid ${\text{K}}_{\text{2}}{\text{Cr}}_{\text{2}}{\text{O}}_{\text{7}}$ is to be described.

Concept introduction: Preparation of particular solution of desired concentration and volume requires certain solute’s mass. This solute’s mass is evaluated by first calculating moles. The solution’s concentration and volume when multiplied results in solute’s moles. This calculated solute’s mass is added to water to obtain the required solution.

(d)

Interpretation Introduction

Interpretation: The preparation of $\text{2}\text{.00}\text{L}$ of $0.100\text{M}{\text{K}}_{\text{2}}{\text{Cr}}_{\text{2}}{\text{O}}_{\text{7}}$ solution from $\text{1}\text{.75}\text{M}{\text{K}}_{\text{2}}{\text{Cr}}_{\text{2}}{\text{O}}_{\text{7}}$ stock solution is to be described.

Concept introduction: The solution possessing greater solute’s concentration is concentrated and the one possessing lower solute’s concentration is dilute. The process of making a dilute solution starting from concentration is referred as dilution. This dilution process is generally done by increasing the solvent’s amount in the solution.