If the buffer says 7.5 and it makes up 6 when mixed, either far too little of the buffer was used/there was already something else buffering the solution or the buffer was prepared incorrectly.
By selecting the correct buffer and the correct ratio of salt to acid (such as acetic acid and sodium acetate) an exact pH within a certain range can be reached.
If the buffer says 7.5 and it makes up 6 when mixed, either far too little of the buffer was used/there was already something else buffering the solution or the buffer was prepared incorrectly.
By selecting the correct buffer and the correct ratio of salt to acid (such as acetic acid and sodium acetate) an exact pH within a certain range can be reached.