Calculating pH of .40M NH4ClO4 Stuck!

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In summary, to calculate the pH of a solution containing .40M NH4ClO4, you will need to use the equation pH = -log[H+]. The [H+] concentration comes from the dissociation of NH4ClO4, which can be found by first determining the initial concentration of NH4ClO4 and using the equilibrium equation for its dissociation. The dissociation constant for NH4ClO4 is 1.3 x 10^-5, and the Henderson-Hasselbalch equation cannot be used to calculate the pH of this solution because NH4ClO4 is a strong acid. The pH of a .40M NH4ClO4 solution is approximately 1.4, and the
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Homework Statement


I was asked to calculate the pH of .40M solution of NH4ClO4

but I wasn't given a Ka for it.


Homework Equations





The Attempt at a Solution



I dissciated NH4ClO4 into:

NH4(plus) and ClO4(minus)

but I"m stuck there. What am I doing wrong?
 
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So far OK. Determine which ion is responsible for pH change. There are pKa (Ka) tables - use them.
 
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it is important to always have the necessary information and data in order to accurately solve a problem. In this case, you are correct in dissociating NH4ClO4 into NH4+ and ClO4- ions. However, in order to calculate the pH of the solution, we need the Ka value for NH4+ and its conjugate acid, NH3. Without this information, it is not possible to accurately solve for the pH. I suggest reaching out to your instructor or referring to a reliable source to obtain the necessary Ka value. Without it, any attempt at solving for the pH would be incorrect. It is important to always have all the necessary information before attempting to solve a problem in order to ensure accurate results.
 

1. How do I calculate the pH of a solution containing .40M NH4ClO4?

To calculate the pH of a solution, you will need to use the equation: pH = -log[H+]. In this case, the [H+] concentration will come from the dissociation of NH4ClO4. To find this value, you will first need to determine the initial concentration of NH4ClO4, which in this case is .40M. Next, use the equilibrium equation for the dissociation of NH4ClO4, which is NH4ClO4 ⇌ NH4+ + ClO4-. This will give you the [NH4+] concentration. Finally, use the [NH4+] concentration to find the [H+] concentration, and then plug that value into the pH equation.

2. What is the dissociation constant for NH4ClO4?

The dissociation constant, also known as the acid dissociation constant (Ka), for NH4ClO4 is 1.3 x 10^-5. This value is used in the equilibrium equation for the dissociation of NH4ClO4 to determine the concentrations of NH4+ and ClO4-.

3. Can I use the Henderson-Hasselbalch equation to calculate the pH of this solution?

No, the Henderson-Hasselbalch equation is only applicable for weak acids or bases. NH4ClO4 is a strong acid, so the Henderson-Hasselbalch equation cannot be used. Instead, you will need to use the pH = -log[H+] equation.

4. What is the pH of a .40M NH4ClO4 solution?

The pH of a .40M NH4ClO4 solution is approximately 1.4. This value can be calculated using the pH = -log[H+] equation, as well as the dissociation equation for NH4ClO4 and the dissociation constant.

5. How does the concentration of NH4ClO4 affect the pH of the solution?

The concentration of NH4ClO4 will affect the pH of the solution because it directly impacts the [NH4+] concentration, which is then used to find the [H+] concentration. The higher the concentration of NH4ClO4, the higher the [NH4+] and [H+] concentrations will be, resulting in a lower pH value.

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