Chapter 5, Problem 5.147P

(a)

Interpretation Introduction

Interpretation:

At STP condition the exposure to ${\text{Br}}_{\text{2}}$ gas at a partial pressure of $0.2\text{torr}$ for $8\text{ h}$ is safe or unsafe is to be determined.

Concept introduction:

The expression to calculate the partial pressure of the gas is as follows:

  $P_{\text{gas}}=X_{\text{gas}}\cdot P_{\text{total}}$

Here, $P_{\text{gas}}$ is the partial pressure of the gas, $X_{\text{gas}}$ mole fraction of the gas and $P_{\text{total}}$ is the total pressure.

The expression to calculate the mole fraction of the gas is as follows,

  $X_{\text{gas}}=\frac{\text{Moles of gas}}{\text{Total moles}}$

Here, $X_{\text{gas}}$ is the mole fraction of the gas.

The ideal gas equation can be expressed as follows,

  $PV=nRT$

Here, $P$ is the pressure, $V$ is the volume, $T$ is the temperature, $n$ is the mole of the gas and $R$ is the gas constant.

(b)

Interpretation Introduction

Interpretation:

The exposure of ${\text{CO}}_{\text{2}}$ gas at a partial pressure of $0.2\text{torr}$ is safe or unsafe is to be determined.

Concept introduction:

The ideal gas equation can be expressed as follows:

  $PV=nRT$

Here, $P$ is the pressure, $V$ is the volume, $T$ is the temperature, $n$ is the mole of the gas and $R$ is the gas constant.

The expression to calculate the partial pressure of the gas is as follows:

  $P_{\text{gas}}=X_{\text{gas}}\cdot P_{\text{total}}$

Here, $P_{\text{gas}}$ is the partial pressure of the gas, $X_{\text{gas}}$ mole fraction of the gas and $P_{\text{total}}$ is the total pressure.

The expression to calculate the mole fraction of the gas is as follows:

  $X_{\text{gas}}=\frac{\text{Moles of gas}}{\text{Total moles}}$

Here, $X_{\text{gas}}$ is the mole fraction of the gas.

(c)

Interpretation Introduction

Interpretation:

The exposure to $1000\text{ L}$ of air that contains $0.0004\text{ g}$ of ${\text{Br}}_{\text{2}}$ gas is safe or unsafe is to be determined.

Concept introduction:

The expression to calculate the moles of solute is as follows:

  $\text{Moles of solute}=\frac{\text{Given mass of solute}}{\text{Molar mass of solute}}$

The ideal gas equation can be expressed as follows,

  $PV=nRT$

Here, $P$ is the pressure, $V$ is the volume, $T$ is the temperature, $n$ is the mole of the gas and $R$ is the gas constant.

(d)

Interpretation Introduction

Interpretation:

The exposure to $1000\text{ L}$ to of air that contains $2.8\times {10}^{22}\text{ molecule}$ of ${\text{CO}}_{\text{2}}$ gas is safe or unsafe is to be determined.

Concept introduction:

The expression to calculate the moles of solute is as follows:

  $\text{Moles of solute}=\frac{\text{Given mass of solute}}{\text{Molar mass of solute}}$

The ideal gas equation can be expressed as follows,

  $PV=nRT$

Here, $P$ is the pressure, $V$ is the volume, $T$ is the temperature, $n$ is the mole of the gas and $R$ is the gas constant