Calculate the ratio of ph of solution containing one mole of ch3coona ...
First 1 there is no buffer since only HCl gives 1 mole of H+ which gives pH -1.
Second One there is buffer where pH=pKa as log 1/1 =0.
pKa =4.75 as Ka=1.75*10^-5 you get the ration as -2.01
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Calculate the ratio of ph of solution containing one mole of ch3coona ...
Calculation of the pH of a solution containing one mole of CH3COONa and one mole of HCl per liter:
To calculate the pH of a solution, we first need to determine the concentration of the ions present in the solution. In this case, we have one mole of CH3COONa and one mole of HCl per liter.
CH3COONa dissociates completely in water to form CH3COO- ions and Na+ ions. Similarly, HCl dissociates completely to form H+ ions and Cl- ions. Therefore, the concentration of CH3COO- ions and H+ ions is one mole per liter.
The dissociation of CH3COOH (acetic acid) in water can be represented by the equation: CH3COOH ⇌ CH3COO- + H+
The equilibrium constant for this reaction is known as the acid dissociation constant (Ka) of acetic acid, which is approximately 1.8 x 10^-5. Using this value, we can calculate the concentration of H+ ions in a solution containing one mole of CH3COO- and one mole of CH3COOH.
The formula for calculating pH is given by: pH = -log[H+]
Calculation of the pH of a solution containing one mole of CH3COONa and one mole of CH3COOH per liter:
In this case, we have one mole of CH3COONa and one mole of CH3COOH per liter. Since CH3COONa is a salt of acetic acid, it will dissociate completely in water to form CH3COO- ions and Na+ ions.
The dissociation of CH3COOH in water can be represented by the equation: CH3COOH ⇌ CH3COO- + H+
As mentioned earlier, the equilibrium constant (Ka) for this reaction is approximately 1.8 x 10^-5. However, in this case, the concentration of CH3COO- ions is one mole per liter, and the concentration of CH3COOH is also one mole per liter.
Using the Ka value, we can calculate the concentration of H+ ions in the solution.
The formula for calculating pH remains the same: pH = -log[H+]
Comparison of the two solutions:
In the first solution, the concentration of H+ ions is one mole per liter, while in the second solution, the concentration of H+ ions can be determined using the Ka value for acetic acid.
Since the concentration of H+ ions is higher in the first solution, the pH of the first solution will be lower compared to the second solution.
Therefore, the ratio of the pH of the first solution to the second solution can be calculated by comparing the pH values obtained using the formula mentioned earlier.
Note: The actual pH values cannot be determined without the specific concentration of H+ ions in the second solution.
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