How Do You Calculate the Molarity of Glacial Acetic Acid?

  • Thread starter Thread starter alingy1
  • Start date Start date
  • Tags Tags
    Molarity
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
5 replies · 4K views
alingy1
Messages
325
Reaction score
0

Homework Statement



Glacial acetic acid has a density of 1.05g/ml and contains 99.51%acetic acid (CH3COOH) by mass. Calculate the molarity of glacial acetic acid.

So, this is a question in my pre-lab that doesn't even count. But, I still want to get it because we have similar questions in exams.

I'm blocked at the first step:
What is molarity?
Is is the total number of moles? or just the number of acetic acid moles?
 
Physics news on Phys.org
It doesn't really help. I'm asking to know if glacial acetic acid is a solution per se. What is the small percentage that makes CH3COOH account for 99.51%? And is that substance taken into any account when you do the calculation of molarity.
 
alingy1 said:
It doesn't really help. I'm asking to know if glacial acetic acid is a solution per se. What is the small percentage that makes CH3COOH account for 99.51%? And is that substance taken into any account when you do the calculation of molarity.

Did you look at the definition of molarity? We aren't concerned with 0.49% but that will be used when calculating molarity. Have a look at the definition, you will get some idea to begin with.
 
Also, if you take a look at the definition, you can apply it even to pure water - that's a very similar situation.
 
Do you know how to find the number of moles of CH3COOH in 1000 mL of glacial acetic acid? That is the same as the molarity.
What is molarity?
moles of constituent (CH3COOH here)/ Liters of solution (glacial acetic acid here)
Is is the total number of moles? or just the number of acetic acid moles?
Only acetic acid.