stupid question about amphiprotic substances (1 Viewer)

Joined
Mar 13, 2015
Messages
100
Gender
Male
HSC
2015
If HCO3^- is an amphiprotic substance meaning it can act as both acid and a base, won't its pH change at the same concentration? because if it acts as a base then wouldn't its pH be above 7 and if it acts as an acid its pH will be below 7
 

Librah

Not_the_pad
Joined
Oct 28, 2013
Messages
916
Location
Sydney Australia
Gender
Male
HSC
2014
Bases are proton acceptors and acids are proton donors by definition, pH is only determined by the concentration of H3O+.
 

Magnoliatient

New Member
Joined
Apr 29, 2015
Messages
9
Gender
Undisclosed
HSC
2015
Amphiprotic substances can act as an acid or base, but not generally in the same conditions.

for example, when NaHCO3 is dissolved in water, it acts as a base, because HCO3- has a greater tendency to accept protons from water than to donate. Hence, pH >7, and will not change once the reaction reaches equlibrium.

However, if HCO3- is reacted with a base, it will have a greater tendency to donate protons, so it is acting as an acid in this case
 

helloimyellow

Active Member
Joined
Sep 12, 2015
Messages
108
Gender
Male
HSC
2015
^ lol this guy

EDIT: woops there was a guy that was spamming notes ad. not meant to belittle someone's answer :/
 
Last edited:

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top