Which of the following pairs of substances, when mixed in any proportion you wish, can be used to prepare a buffer solution?

1)NaCN and NaOH
2) HCl and NaOH
3) HCN and NaOH
4)HCl and NaCN
5) NaCN and HCN

is the answer 1 and 5??

chem - DrBob222, Sunday, April 10, 2011 at 1:28am
I don't believe 1 will do it.
Yes on 5. Also 3.
Buffers are weak acid and salt or weak base and salt.
HCN and NaOH can prepare the salt and have HCN left over.
NaCN is the salt HCN for the acid.

chem - Rachel, Sunday, April 10, 2011 at 2:18pm
I tried those and it was wrong

1 answer

5 can be made to a buffer. 3 can be made to a buffer. That means there must be another one since I assume you are keying this into a data base and you must have ALL of the problem right or it is counted wrong. I would look for another one if I were you. By the way, you KNOW 2 can't be one of them.