hydroxide ion concentration when pOH=0.5

To find the hydroxide ion concentration when pOH=0.5, we can first calculate the pH using the formula:

pH + pOH = 14

Therefore, pH = 14 - pOH
= 14 - 0.5
= 13.5

Now that we have the pH, we can calculate the hydrogen ion concentration using the formula:

[H+] = 10^(-pH)
= 10^(-13.5)
≈ 3.16 x 10^(-14) mol/L

Finally, we can find the hydroxide ion concentration using the formula:

[OH-] = Kw / [H+]
= 1.0 x 10^(-14) / 3.16 x 10^(-14)
≈ 3.16 x 10^(-1) mol/L
≈ 0.316 mol/L

Therefore, the hydroxide ion concentration when pOH = 0.5 is approximately 0.316 mol/L.