2012年2月12日星期日

What are the disadvantages of litmus paper rather than red cabbage juice as an indicator?

Please reply quick for my cousin's lab report!
What are the disadvantages of litmus paper rather than red cabbage juice as an indicator?
I would say that the paper is a little more in price, but not difficult to find. Chemically speaking:



1.) with cabbage juice, you cannot determine the exact pH of the particular solution. The paper goes by a wet color system that is pretty good the about one decimal point. But it does the job.



2.) Just say if you did a tritration against a particular solution with cabbage juice. You will find that there will be no color change until AFTER the neutralization point. This is where you have an excess of one ion versus the other.

Don't kid me wrong, when I say that you cannot get the pH or concentration of ion in a solution. You can do calculations for that. But I am just saying that the paper is a lot faster.
Reply:pricier/harder to find

没有评论:

发表评论