What would be the pH of a soda water made by saturating pure water with pure CO2 at 1 atm pressure?

If we call the (H2CO3) = 0.034M, then

...........H2CO3 ==> H^+ + HCO3^-
I..........0.034......0......0
C..........-x.........x......x
E..........0.034-x.....x.....x

Substitute the E line into k1 for H2CO3 (look that up in your text tables) and solve for x = (H^+) then convert to pH.

To determine the pH of soda water made by saturating pure water with pure CO2 at 1 atm pressure, we need to consider how carbon dioxide reacts with water to form carbonic acid.

The reaction can be represented as follows:

CO2 + H2O ⇌ H2CO3

Carbonic acid (H2CO3) is a weak acid that dissociates partially in water. When it does, it releases hydrogen ions (H+), which contribute to the acidity of the solution. The pH scale measures the concentration of hydrogen ions in a solution, with lower pH values indicating greater acidity.

Since carbonic acid is a weak acid, we can assume it only partially dissociates. However, we need additional information to calculate the exact pH of soda water made under these conditions. The concentration of dissolved carbon dioxide, temperature, and dissociation constant of carbonic acid at 1 atm pressure are needed to determine the pH accurately.

Without this specific information, we cannot provide an exact pH value. The pH may vary depending on these factors and the presence of other ions or impurities in the water.

To determine the pH of soda water made by saturating pure water with pure CO2 at 1 atm pressure, we need to consider the reaction that occurs when carbon dioxide dissolves in water. When CO2 dissolves, it reacts with water to form carbonic acid (H2CO3), which undergoes partial dissociation.

The balanced equation for this process is:

CO2 (g) + H2O (l) ⇌ H2CO3 (aq)

Carbonic acid, in turn, dissociates partially into hydrogen ions (H+) and bicarbonate ions (HCO3-), as described by the following equilibrium equation:

H2CO3 (aq) ⇌ H+ (aq) + HCO3- (aq)

Since we are dealing with pure carbon dioxide and pure water, we can assume the initial concentration of CO2 is directly proportional to its pressure. Therefore, when CO2 dissolves in water at 1 atm pressure, it creates a specific concentration of carbonic acid.

Now, the pH of a solution is a measure of the concentration of hydrogen ions (H+). It is defined as the negative logarithm (base 10) of the hydrogen ion concentration. Mathematically, pH can be calculated as:

pH = -log[H+]

To determine the pH of soda water made by saturating pure water with pure CO2 at 1 atm pressure, we need to analyze the concentration of hydrogen ions (H+), which is determined by the concentration of carbonic acid (H2CO3) in the solution.

Without experimental data, it is difficult to provide an exact pH value. However, as a general guideline, soda water typically has a pH of around 3 to 4. This means it is slightly acidic due to the presence of carbonic acid, which is a weak acid.

To obtain a more precise pH value, one would need to know the solubility of carbon dioxide in water at a specific temperature and the subsequent dissociation constants of carbonic acid. Additionally, experimental measurements or further calculations can help determine the actual concentration of hydrogen ions and, therefore, the pH of the soda water.