# Chemistry

posted by .

The pH of 0.50 M HBrO(aq) is 4.50. Calculate the change in pH when 6.50 g of sodium hypobromite is added to 110. mL of the solution. Ignore any change in volume. Ka of HBrO is 2E-9

I found the amount of moles used for each (.0547 mol NaBrO, and .055 mol HBrO soln)

I'm not totally sure how to find the new pH. Do I set up an ICE chart? If I do...I'm not sure how to set up the expression for the addition of NaBrO to HBrO...

• Chemistry -

I am trying to use pH=pKa + log(acid/base) to see where that gets me...I'm attempting to find the [base] using the given pH and pKa of 8.69 (for HBrO)...then use the concentration to find the new pH...

• Chemistry -

You can use the Henderson-Hasselbalch equation to calculate pH or you can set up the Ka expression and substitute (HBrO) where needed and use (NaBrO) as (BrO^-) in the Ka expression. Calculate H^+ and pH from that.

• Chemistry -

I am pretty stuck...not sure if I used the Henderson-Hasselbach the right way and I'm a little confused on how to set up the Ka expression...

• Chemistry -

Nevermind I got it...I just mixed up my variables a little. thanks!

• Chemistry -

First, a correction. The H-H equation is
pH = pKa + log (base/acid); your fraction is invered incorrectly.

Here are both ways:
HBrO ==> H^+ + BrO^-

Ka = 2 x 10^-9 = (H^+)(BrO^-)/(HBrO)
Plug in (BrO^-) 6.50grams/molar mass NaBrO and that divided by 0.110 L. (HBrO) = 0.5 M and solve for H^+ then convert to pH.

The HH equation is easier.
pKa = 8.70 rounded a little but you need to confirm that.
pH = pKa + log (base/acid)
Plug in Ka, (base) = 6.5/molar mass NaBrO and divide by 0.110 L. For acid plug in 0.5 M. I get pH about 7.7 or so.

## Similar Questions

1. ### Chemistry

What is the pH of a 0.200M solution for HBrO?
2. ### Chemistry

What is the pH of a 0.200M solution for HBrO?
3. ### Chemistry

A 30.00ml sample of 0.1234 M hypobromous acid (HBrO) is titrated with a 0.2555 M KOH solution. The Ka for HBrO is 2.5*10^-9 Calculate the pH of the titration mixture at the equivalence point.
4. ### Food Chemistry

Calculate the amounts and pH values for preparing the following acetic acid/acetate buffer solution. 1.) In the first step, If you plan to prepare a 2.00 M sodium acetate in 200.0 mL distilled water, how many grams of sodium acetate …
5. ### chemistry

a titration is done with with 25.00 mL of a .1500 M HBrO solution is titrated with .1025 M NaOH. Ka for HBrO= 2.0 x10^-9. The pH of HBrO before the titration begins is approx. closest to which of the following a. 0.82 b. 4.76 c. 8.70 …
6. ### chemistry

The pH of a 0.55-M aqueous solution of hypobromous acid, HBrO, at 25°C is 4.48. What is the value of Ka for HBrO?
7. ### Chemistry

What is the pH of a 0.94 M solution of HBrO that is also 0.59 M in magnesium hypobromite, the salt of it's conjugate base?
8. ### Chemistry

Assume equal concentrations, rank these solutions by pH HBrO, Ca(OH)2, HCl, KOH, NH3 Here's how I ranked it: highest: Ca(OH)2 > HCl > KOH > NH3 > HBrO lowest is this correct?
9. ### Chemistry

What is the pH of a 0.350M HBrO Solution?
10. ### Chemistry

The pH of 0.40 M HF(aq) is 1.93. Calculate the change in pH when 0.301 g of sodium fluoride is added to 53.7 mL of the solution. Ignore any change in volume.

More Similar Questions