Question

What is the henry's law constant for co2 at 20∘c? express your answer to three significant figures and include the appropriate units?

Answer 1

Actually, Henry's Law is an empirical value. It means that it was not obtained out of raw calculations or correlations. This was gathered from experimental results. Hence, you can search its data. At standard temperature of 25°C (298 K),

k = k°e^[2400(1/T - 1/T°)], where k° = 29.4 L·atm/mol
Substituting the values so that T would be in 20°C or 293 K,
k = (29.4 L·atm/mol)e^[2400(1/293 - 1/298)]
k = 33.7 L·atm/mol

Answer 2

The value of Henry’s law constant for ${\text{C}}{{\text{O}}_{\text{2}}}$ at $20{\text{ }}^\circ {\text{C}}$ is $\boxed{3.70 \times {{10}^{ - 2}}{\text{ L}} \cdot {\text{atm}} \cdot {\text{mo}}{{\text{l}}^{ - 1}}}$.

Further explanation:

Solubility

It is that property of substance by virtue of which it becomes able to dissolve in other substances. It is measured in terms of the maximum amount of solute that can be dissolved in the given amount of solvent.

Henry’s Law

According to this law, solubility of gas dissolved in the liquid is directly related to the partial pressure of gas. High partial pressure means high solubility and vice-versa.

Mathematically,

${{\text{S}}_{{\text{gas}}}} \propto {{\text{P}}_{{\text{gas}}}}$  …… (1)                                                                                    

To remove the proportionality constant in equation (1), constant known as Henry’s constant is incorporated and equation (1) modifies to,

${{\text{S}}_{{\text{gas}}}} = {{\text{k}}_{\text{H}}}{\mathbf{ \times }}\;{{\text{P}}_{{\text{gas}}}}$         …… (2)                                                                      

Here,

${{\text{S}}_{{\text{gas}}}}$ is the solubility of gas.

${{\text{k}}_{\text{H}}}$ is Henry’s constant.

${{\text{P}}_{{\text{gas}}}}$ is the pressure of gas.

Equation (2) can be rearranged in order to calculate Henry’s constant $\left( {{{\text{k}}_{\text{H}}}} \right)$ and equation (2) becomes,

${{\text{k}}_{\text{H}}} = \dfrac{{{{\text{S}}_{{\text{gas}}}}}}{{{{\text{P}}_{{\text{gas}}}}}}\;$    …… (3)                                                                                  

At $20{\text{ }}^\circ {\text{C}}$ , the value of Henry’s law constant for ${\text{C}}{{\text{O}}_{\text{2}}}$ up to three significant figures is $3.70 \times {10^{ - 2}}{\text{ L}} \cdot {\text{atm}} \cdot {\text{mo}}{{\text{l}}^{ - 1}}$.

Learn more:

1. What is the concentration of alcohol in terms of molarity? https://brainly.com/question/9013318
2. Determine whether solubility will increase, decrease or remains the same: https://brainly.com/question/2802008

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Solutions

Keywords: solubility, gas, Henry’s law, partial pressure, solubility, dissolve, CO2, three significant figures, $3.70*10^-2 L atm/mol,$ high partial pressure, high solubility.