Chapter 3, Problem 35E

(a)

Interpretation Introduction

Interpretation: The number of moles of $20.0\text{mg}$ caffeine $\left({\text{C}}_8{\text{H}}_{10}{\text{N}}_4{\text{O}}_2\right)$ is to be calculated.

Concept introduction: The theory using which any substance’s quantity as its moles can be interpreted is addressed as mole concept.Molar mass value corresponding to the substance in addition to its mass should be known to evaluate its respective moles. Numerically, it is computed by using equation $\text{Moles}=\text{Given}\text{mass/Molar}\text{mass}$ .

(b)

Interpretation Introduction

Interpretation: Thenumber of moles of $2.72\times {10}^{21}$ molecules of ethanol $\left({\text{C}}_2{\text{H}}_5\text{OH}\right)$ is to be calculated.

Concept introduction:The theory using which any substance’s quantity as its moles can be interpreted is addressed as mole concept. Molar mass value corresponding to the substance in addition to its mass should be known to evaluate its respective moles. Numerically, it is computed by using equation $\text{Moles}=\text{Given}\text{mass/Molar}\text{mass}$ .

(c)

Interpretation Introduction

Interpretation: The number of moles of $1.50\text{g}$ of dry ice $\left({\text{CO}}_2\right)$ is to be calculated.

Concept introduction:The theory using which any substance’s quantity as its moles can be interpreted is addressed as mole concept. Molar mass value corresponding to the substance in addition to its mass should be known to evaluate its respective moles. Numerically, it is computed by using equation $\text{Moles}=\text{Given}\text{mass/Molar}\text{mass}$ .