By inspection, what is the concentration of H⁺ in a solution that has a pOH of 5.000?
The correct answer and explanation is:
To find the concentration of H+H^+ (hydrogen ions) in a solution when the pOH is known, you can follow these steps:
Step 1: Understand the relationship between pH and pOH.
The pH and pOH of a solution are related by the equation: pH+pOH=14pH + pOH = 14
This relationship comes from the fact that the sum of the pH and pOH in water at 25°C is always 14. Therefore, if you know the pOH, you can easily calculate the pH.
Step 2: Calculate the pH.
Given that the pOH is 5.000, you can use the equation above to find the pH: pH=14−pOH=14−5.000=9.000pH = 14 – pOH = 14 – 5.000 = 9.000
Step 3: Find the concentration of H+H^+.
The pH is related to the concentration of hydrogen ions by the equation: pH=−log[H+]pH = -\log [H^+]
Where [H+][H^+] is the concentration of hydrogen ions in moles per liter. To find [H+][H^+], you can rearrange the equation: [H+]=10−pH[H^+] = 10^{-pH}
Substitute the value of pH into this equation: [H+]=10−9.000=1.0×10−9 M[H^+] = 10^{-9.000} = 1.0 \times 10^{-9} \, \text{M}
Final Answer:
The concentration of H+H^+ is 1.0×10−9 M1.0 \times 10^{-9} \, \text{M}.
Explanation:
The pH of a solution tells you the concentration of hydrogen ions, and since pOH and pH are linked, knowing the pOH allows you to calculate the pH. Once you have the pH, you can use the formula [H+]=10−pH[H^+] = 10^{-pH} to determine the hydrogen ion concentration. In this case, with a pOH of 5.000, the corresponding pH is 9.000, leading to a hydrogen ion concentration of 1.0×10−9 M1.0 \times 10^{-9} \, \text{M}, which indicates the solution is weakly basic.