home > q&a board > chemistry > topic: acidity

Q BgQuestion:

Scholar
Karma Points: 200
Respect (93%):
posted by  tasty on 6/9/2008 7:33:06 PM  |  status: Live  

Acidity

Course Textbook Chapter Problem
Organic Chemistry N/A N/A N/A
Question Details:
Consider the set of compounds, H2O, CH3NH2, and HCl. Rank these componds in order of increasing acidity. Justify your choice.
 
Bonus Point Alert! Earn +2 additional karma points for helping this monthly member.

AAnswers:

Answer Question
Novice
Karma Points: 15
posted by Anonymous on 6/9/2008 7:59:04 PM  |  status: Live
Asker's Rating: Helpful   
tasty's comment:
"thanks for your reply"
Response Details:
HCL dissociates its electrons more completely than CH3NH2.  We of course know that H2O is neutral.  Also, CH3 is less electron withdrawing than H,  so CH3NH2 is a weaker.
Mentor
Karma Points: 546
posted by unified.kiran on 6/9/2008 8:19:46 PM  |  status: Live
Asker's Rating: Lifesaver   
tasty's comment:
"thanks for the detailed answer"
Response Details:
Hi,
The order is :
1) HCl
2) H2O
3) CH3NH2

Note that Amines do contain lone pair of electrons and hence they are electron pair donar,
which is a base according to Lewis theory, that means they are weak acids.

In water though Oxygen has two pairs of electrons, Oxygen is more electro negative and hence the nature can be explained better by Arrhenius or Bronsted - Lowry theories, according to which water acts as an acid and as a base depends on the nature of other substance.

I hope this helps.
Good luck.
Scholar
Karma Points: 226
posted by ScienceGeek on 6/9/2008 9:33:58 PM  |  status: Live
Asker's Rating: Helpful   
tasty's comment:
"Yes, thanks for letting me know the basic of pH values."
Response Details:
Think of hydrochloric acid as being the most acidic with a very low pH, water is usually close to neutral, and the amine groups (such as ammonia) being basic with higher pH then the previous two.
Answer Question
Ask New Question

Join Cramster's Community

Cramster.com brings together students, educators and subject enthusiasts in an online study community. With around-the-clock expert help and a community of over 100,000 knowledgeable members, you can find the help you need, whenever you need it. Join for free today » How Cramster is different than tutoring »

Need Help In

Useful Links