pH Buffer solution

[disneychannel]

I have no idea how to find the pH of a buffer solution:
Please step by step!
Calculate the pH after 0.020 mol NaOH is added to 1.00 L of:
a mixture containing 0.100 M HONH2 and 0.100 M HONH3Cl

please step by step instruction so I can follow and do other problems on my own! Thanks

[dacruick]

its been a while but dont you just find the moles of each. then find out how many OH or H you have and find the ph like that? or was that not buffer?

[disneychannel]

i don't believe that's how you do it

[Borek]

One of the substances listed reacts with NaOH. Assume reaction is quantitative, then it is just Henderson-Hasselbalch equation (http://www.chembuddy.com/?left=pH-calculation&right=pH-buffers-henderson-hasselbalch).

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buffer calculator (http://www.chembuddy.com/?left=Buffer-Maker&right=buffer-calculator), concentration calculator (http://www.chembuddy.com/?left=CASC&right=concentration_and_solution_calculator)
pH calculator (http://www.chembuddy.com/?left=BATE&right=pH-calculator), stoichiometry calculator (http://www.chembuddy.com/?left=EBAS&right=equation-balancing-stoichiometry)

[disneychannel]

would the answer be 6.18?

[dacruick]

ahhh the henderson hasslebach i remember that one. Yeah you just have to use that equation with the mols of acid and base taht you have.

[Borek]

Depends on what value you have used for pKa. Correct ball park for sure.

--
buffer calculator (http://www.chembuddy.com/?left=Buffer-Maker&right=buffer-calculator), concentration calculator (http://www.chembuddy.com/?left=CASC&right=concentration_and_solution_calculator)
pH calculator (http://www.chembuddy.com/?left=BATE&right=pH-calculator), stoichiometry calculator (http://www.chembuddy.com/?left=EBAS&right=equation-balancing-stoichiometry)