Ka value

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Rebecca Epner 4A
Posts: 53
Joined: Sat Aug 17, 2019 12:18 am

Ka value

Postby Rebecca Epner 4A » Wed Dec 04, 2019 11:49 am

Why does each subsequent Ka value decrease significantly? In class I wrote Ka1 > Ka2 > Ka3 because it is harder to lose H+ from a negatively charges ion but can someone explain this further?

Abigail Sanders 1E
Posts: 112
Joined: Wed Sep 11, 2019 12:16 am

Re: Ka value

Postby Abigail Sanders 1E » Wed Dec 04, 2019 12:00 pm

Once the molecule loses one H+ ion, it normally now has a negative charge. Because negatively charged atoms attract positively charged ones it will be increasingly harder to lose another positive charge as the molecule would like to remain as stable and as neutral as possible. Thus, the additional H+ are hard to lose as molecules like to have neutral charges as they are favorable in stability.

Sears 4A
Posts: 36
Joined: Tue Feb 05, 2019 12:15 am

Re: Ka value

Postby Sears 4A » Wed Dec 04, 2019 8:08 pm

yeah as a molecule gains electrons, it becomes hard for the molecule to gain more, making the kA lower

Posts: 101
Joined: Fri Aug 30, 2019 12:17 am

Re: Ka value

Postby AronCainBayot2K » Wed Dec 04, 2019 9:24 pm

Ka values will decrease the more negatively charged the ion becomes. The H+ ion would be harder to lose thus Ka1 would be the greatest.

Posts: 100
Joined: Tue Oct 08, 2019 12:16 am

Re: Ka value

Postby Micah3J » Wed Dec 04, 2019 9:36 pm

This is only in regard to resulting molecules and Ka calculations right?

Sanjana Borle 2K
Posts: 111
Joined: Fri Aug 09, 2019 12:15 am

Re: Ka value

Postby Sanjana Borle 2K » Wed Dec 04, 2019 9:36 pm

Does Ka 3 mean Ka1 plus Ka2? Is is the overall Ka for the reaction?

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