kh values for ar,co2,hcho and ch4 are 40-39,1-67,1,83*10^-5 and 0.413 respectively.arrange these gases in the order of their increasing solubility

To determine the order of increasing solubility for the gases you mentioned—argon (Ar), carbon dioxide (CO2), formaldehyde (HCHO), and methane (CH4)—we can look at their Henry's law constants (kH values). The kH value indicates how much of a gas will dissolve in a liquid at a given temperature; lower kH values correspond to higher solubility in water. Here are the kH values you provided for each gas:

• Argon (Ar): 40
• Carbon Dioxide (CO2): 39.1
• Formaldehyde (HCHO): 1.83 x 10^-5
• Methane (CH4): 0.413

Now, let's analyze these values. The gases can be arranged in order of increasing solubility based on their kH values:

Understanding Solubility and kH Values

In this context, a lower kH value indicates that the gas is more soluble in water. Therefore, we can rank the gases from the lowest kH value to the highest:

Ranking the Gases

• Formaldehyde (HCHO): 1.83 x 10^-5 (most soluble)
• Methane (CH4): 0.413
• Carbon Dioxide (CO2): 39.1
• Argon (Ar): 40 (least soluble)

Thus, the order of increasing solubility is:

1. Argon (Ar)
2. Carbon Dioxide (CO2)
3. Methane (CH4)
4. Formaldehyde (HCHO)

Why This Order Makes Sense

The solubility of gases in water is influenced by several factors, including molecular size, polarity, and the presence of functional groups. For instance:

• Formaldehyde is a polar molecule with a functional group that can interact favorably with water, making it highly soluble.
• Methane is non-polar but has a relatively low molecular weight, allowing for some solubility.
• Carbon Dioxide can react with water to form carbonic acid, which contributes to its solubility, but its kH value is still higher than that of formaldehyde and methane.
• Argon is a noble gas with a complete electron shell, making it very non-polar and thus the least soluble in water.

In summary, when considering the kH values, we see that formaldehyde is the most soluble gas among the ones listed, while argon is the least soluble. This ranking reflects the underlying chemistry of each gas and its interaction with water.