Is My Acid-Base Mixture Actually Neutral?

[david2120]

In my chmeistry lab i use a pipet 5.0 ml of HCl and add it to a beaker. To this beaker I also added 5.0 ml NaOH. I stir the mixture and when a red litmus it turn to blue and when i put a blue litmus it stay blue. So that means its a base, but since its a mixture of an acid and a base shouldn't it be neutral? Did I do something wrong or is it correct?

 

[Hootenanny]

If your pH test are showing an alkaline solution, then you have either added too much Sodium Hydroxide or the Sodium Hydroxide is more concentrated than the Hydrochloric Acid. In my experience you never get exactly a neutral solution, you tend to go a bit too far.

 

[Borek]

Assuming you measured volumes with 1% accuracy (not bad) your solution may contain up to 2% excess of one of the reagents. Assuming 0.1M solutions your pH can be anywhere between 3.00 and 11.00 - looks like you have overshot

 

[david2120]

well my lab teacher provided the Hcl and NaOH so we don't know how concentrated it is. She only told us to use 5 ml of each and when I put the red litmus it turn blue which means its base. So from my understanding Naoh is more concentrated then HCl since they both had the same amount of ml. Am I Correct?

 

[Hootenanny]

Yes, assuming of course that you added the same amount, the pipette will have a standard error associated with the volume.