12.17  [ENDORSED]

Moderators: Chem_Mod, Chem_Admin

Sarah Rutzick 1L
Posts: 50
Joined: Tue Oct 10, 2017 7:13 am

12.17

Postby Sarah Rutzick 1L » Sat Dec 02, 2017 4:04 pm

State whether the following oxides are acidic, basic, or amphoteric: a) BaO b) SO3 c) As2O3 d) Bi2O3

How do you tell what these are, particularly how do you know when they're amphoteric?

Chem_Mod
Posts: 17949
Joined: Thu Aug 04, 2011 1:53 pm
Has upvoted: 406 times

Re: 12.17

Postby Chem_Mod » Sat Dec 02, 2017 4:13 pm

The general rule is that nonmetal oxides are acidic, metal oxides are basic, and semimetal oxides are amphoteric.

David Minasyan 1C
Posts: 54
Joined: Thu Jul 13, 2017 3:00 am

Re: 12.17  [ENDORSED]

Postby David Minasyan 1C » Sat Dec 02, 2017 4:15 pm

You can always try drawing out lewis structures and seeing if the compound can give, receive, or both give and receive lone pairs. If it can do both then its amphoteric. That's how I'd go about it - I dont really know of any other way.

dstemp
Posts: 20
Joined: Fri Sep 29, 2017 7:07 am

Re: 12.17

Postby dstemp » Sat Dec 02, 2017 5:54 pm

If metal oxides are basic, why is Bi2O3 amphoteric? Since Bismuth is a metal. Is the metal oxides being basic simply a general rule with certain exceptions?

Jessica Lutz 2E
Posts: 56
Joined: Fri Sep 29, 2017 7:04 am

Re: 12.17

Postby Jessica Lutz 2E » Sat Dec 02, 2017 8:22 pm

David Minasyan 1G wrote:You can always try drawing out lewis structures and seeing if the compound can give, receive, or both give and receive lone pairs. If it can do both then its amphoteric. That's how I'd go about it - I dont really know of any other way.


How can you tell by looking at the lewis structure if a compound can give and/or receive lone pairs?

Andy Liao 1B
Posts: 52
Joined: Thu Jul 13, 2017 3:00 am

Re: 12.17

Postby Andy Liao 1B » Sat Dec 02, 2017 11:44 pm

Jessica Lutz 1C wrote:
David Minasyan 1G wrote:You can always try drawing out lewis structures and seeing if the compound can give, receive, or both give and receive lone pairs. If it can do both then its amphoteric. That's how I'd go about it - I dont really know of any other way.


How can you tell by looking at the lewis structure if a compound can give and/or receive lone pairs?


I learned in my discussion section that a structure with a lone pair is a Lewis base and a structure with an incomplete octet is a Lewis acid.

Julia Meno 1D
Posts: 28
Joined: Fri Sep 29, 2017 7:04 am

Re: 12.17

Postby Julia Meno 1D » Mon Dec 04, 2017 8:16 pm

Can someone explain why Bi2O3 is amphoteric? It's technically not listed as a metalloid on the periodic table.

RenuChepuru1L
Posts: 58
Joined: Thu Jul 27, 2017 3:00 am

Re: 12.17

Postby RenuChepuru1L » Fri Dec 08, 2017 12:38 am

Julia Meno 1D wrote:Can someone explain why Bi2O3 is amphoteric? It's technically not listed as a metalloid on the periodic table.

draw out the lewis structure

Jonghwee Park 1K
Posts: 30
Joined: Fri Apr 06, 2018 11:04 am

Re: 12.17

Postby Jonghwee Park 1K » Thu Jun 14, 2018 2:18 pm

How does the lewis structure prove that it can receive or give away lone pairs?

Chem_Mod
Posts: 17949
Joined: Thu Aug 04, 2011 1:53 pm
Has upvoted: 406 times

Re: 12.17

Postby Chem_Mod » Thu Jun 14, 2018 3:59 pm

There has been a previous answer regarding this on chemistry community that can be found here: viewtopic.php?t=610

Now, how to tell whether or not it can react with both an acid or a base, in the case f the somewhat interesting examples of As2O3 and Bi2O3, the two metalloid components are able to separate to form coordination compounds where its oxygens have been protonated to waters that coordinate or where hydroxide ions coordinate.


Return to “Amphoteric Compounds”

Who is online

Users browsing this forum: No registered users and 1 guest