lecture 5 question

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Heather Costa 2C
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lecture 5 question

Postby Heather Costa 2C » Wed Jan 13, 2021 1:51 pm

i had a different professor so it was taught a little different but for weak/strong acids and bases should we have them memorized for this class? also can someone explain conjugate base/acid ?

OwenSumter_2F
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Re: lecture 5 question

Postby OwenSumter_2F » Wed Jan 13, 2021 1:54 pm

Yes, you'll have to memorize the strong acids and bases, they should be in your textbook. As for conjugate bases/acids, they are what's left of an acid/base respectively after taking away or adding an H+

Marisa Gaitan 2D
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Re: lecture 5 question

Postby Marisa Gaitan 2D » Wed Jan 13, 2021 1:59 pm

I think it would be important to memorize all the strong acids and bases. That way, when coming across any other acid/base, you will know it has to be weak. A conjugate acid is the product formed when a base reacts with water. A conjugate base is the product formed when an acid reacts with water. For example, in the reaction, NH4+(aq) + H2O(l) --> NH3(aq) + H3O+(aq), NH4+ is the acid reacting with water, so the conjugate base is NH3. Hope this helps!

Inderpal Singh 2L
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Re: lecture 5 question

Postby Inderpal Singh 2L » Wed Jan 13, 2021 2:31 pm

I think you should have most of them memorized. However, when you do enough practice with these types of problems, they become increasingly easier to identify I've found!

Brianna Chen 3F
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Re: lecture 5 question

Postby Brianna Chen 3F » Fri Jan 15, 2021 1:15 am

Yes! Memorizing them really helps. I would memorize the strong acids and know that strong bases are usually Group 1/2 elements with an oxide (—O) or hydroxide (—OH) attached.

Queena Chu 3E
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Re: lecture 5 question

Postby Queena Chu 3E » Fri Jan 15, 2021 1:20 am

I definitely recommend memorizing them! Using a chart at first will really help but it definitely gets easier as you practice :)

Mackenzie Stockton 2H
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Re: lecture 5 question

Postby Mackenzie Stockton 2H » Fri Jan 15, 2021 11:24 am

Yes, there are trends (like group 1 and 2 metal oxides/hydroxides are strong bases) and also specific strong acids and bases you should memorize, found in the textbook.

When an acid protonates, it forms is conjugate base. When a base accepts the H+, it forms its conjugate acid. Heres an example:

HCl + H20 --> Cl- + H30+
HCL is the acid here (a strong acid). When it gives off its H+, it becomes Cl- (the conjugate base). Also note that since HCl is a strong acid, its conjugate base (Cl-) is very weak because HCl is almost 100% ionized in solution and therefore the reverse reaction rarely (if ever) takes place.

Olivia Monroy 1A
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Re: lecture 5 question

Postby Olivia Monroy 1A » Fri Jan 15, 2021 11:31 am

Always better to memorize! That way when you come across something that is neither a strong acid or base you can figure it to be weak. Strong acids include HCl, HBr, HI... and strong bases are group 1/2 elements with oxide/hydroxide attached including LiOH, NaOH, KOH...

FionaHunter21
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Re: lecture 5 question

Postby FionaHunter21 » Fri Jan 15, 2021 11:55 am

I think he wants us to know the strong acids and bases that are listed in the book. In an equation, the conjugate base/acid is the base/acid once it has lost or gained a proton.

Ivy Tan 1E
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Re: lecture 5 question

Postby Ivy Tan 1E » Fri Jan 15, 2021 12:24 pm

Hi!
I think you have to memorize the strong acids and bases for this class. This is a mnemonic I learned to help me memorize the strong acids: So I Brought No Clean Clothes. So=H2SO4, I=HI, Br=HBr, No=HNO3, Cl=HCl and HClO4. Hopefully this makes it a little easier to memorize!
Also, conjugate bases are the species formed after an acid loses a proton and conjugate acids are the species formed after a base accepts a proton. Hope this helps!

Melis Kasaba 2B
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Re: lecture 5 question

Postby Melis Kasaba 2B » Fri Jan 15, 2021 1:04 pm

Yes, Lavelle said that we should memorize the strong acids and bases, and then by knowing those, we can conclude every other acid or base we see is weak. A conjugate base of a Bronsted-Lowry acid is formed after an acid donates a proton. A conjugate acid of a Bronsted-Lowry base is the species formed after a base accepts a proton. In a conjugate acid-base pair, the two species have the same molecular formula, except the acid has an extra H+ (proton) compared to the conjugate base.

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Heather Costa 2C
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Re: lecture 5 question

Postby Heather Costa 2C » Fri Jan 15, 2021 3:12 pm

so the conjuagate base or acid kind of correlate to the acid/base?

Amanda Chang 2B
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Re: lecture 5 question

Postby Amanda Chang 2B » Fri Jan 15, 2021 3:55 pm

Heather Costa 2C wrote:so the conjuagate base or acid kind of correlate to the acid/base?


Yup! A conjugate base is formed by the removal of a proton from an acid and a conjugate acid is formed by the addition of a proton to a base.

SavannahScriven_1F
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Re: lecture 5 question

Postby SavannahScriven_1F » Fri Jan 15, 2021 4:51 pm

A conjugate base is formed when an acid protonates a solution. The compound loses its H, so it now has the ability to accept an H. This is the definition of a bronsted base. The word "conjugate" is there because the base formed from a different compound (the original acid).


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