Talk:Base (chemistry)

Comments

The amino group (NH₂⁻) acts as a base by accepting a H⁺ ion from the solution. It does this by forming a coordinate covalent bond with the unshared pair of electrons belonging to the nitrogen atom. This decreases the hydrogen ion concentration.

This subject is rather 'basic', so I think the article should be targeted at readers with little chemical background. Therefore I replaced the above example with the simpler case of ammonia.
—Herbee 17:28, 2004 Mar 9 (UTC)

I really liked this page it was very helpful!

THe reactions show hydrogen ions, but the wording says hydronium

maybe we should change the equations to have H30+

I had not seen H₃O⁺ before. I am much more familiar with hydrogen nuclei, H⁺, in acids - Andrew.

Out of curiosity, are strong bases just as dangerous (if not more) as strong acids to objects and, more importantly, humans? —Jay

I believe so, yes. Amonia (I think) is a base, and I know it's dangerous when inhaled. Also, drinking a base could kill you. ;)

The Slash 05:21, 5 May 2006 (UTC)

can denature proteins?

therefore more dangerous than acids?

  acids can too  — Preceding unsigned comment added by 98.229.64.229 (talk) 02:55, 28 February 2012 (UTC) 

strong base merger

There is not much content in strong base, hence why I put the merger up. Thoughts? Olin 22:15, 2 March 2006 (UTC)

I agree. There isn't any point to having an article devoted to 'strong bases'. Jgassens 17:36, 14 March 2006 (UTC)

they should be merged, as strong bases are learnt when you learn about bases.

I agree, but I also think that [Strong acid] should be merged with [Acid] as well, for consistency's sake

The Slash 05:19, 5 May 2006 (UTC)

I agree. But what about Superbase and Superacids ? Cubbi 16:35, 4 April 2007 (UTC)

If so, strong/weak bases would have to be merged into Base, and strong/weak acid would have to be merged with acid. It may be easier to get information if all were kept separate. As a student looking for information on strong bases in particular, the link on the sideba was very useful. This information would be less easily found if merged. Belenus 20:43, 29 May 2006 (UTC)

info in acids page

there is info in acids page about bases that could be put here. thoughts? --nkayesmith 10:41, 5 March 2006 (UTC)

i agree also!

I too agree that the section on Definitions of Acids & Bases could be basically copied here and then eggs are so delicious. --Dawn Burn 04:37, 19 June 2006 (UTC)

About soap

Is really soap is a kind of alkali?Martin 04:24, 14 May 2006 (UTC)

No, bases actually react with your hand oils to make a kind of soap. So they are only soapy when you touch them with bare hands.

I knew that, but why the article says that soap is a kind of base?

Well, soap is definitely slippery (that stuff does actually eat away the oils from your skin, why it is so slippery), bitter tasting (don't swallow!), and I believe one of its ingredients persay is lye, a really strong base. Does that explain anything? David Martin Chao 04:08, 8 May 2007 (UTC)

soap (in its simplest form) is simply a salt of a fatty acid, for example sodium stearate. It has a basic pH because it's a salt of a weak acid and a strong base. Lye (NaOH or KOH) isn't an ingredient, it's a reagent used to neutralize the fatty acids when making soap. And yes, that's what seems to happen on your skin when you touch a strong base - it reacts with your oils making soap (which is slippery because it's a surfactant which has nothing to do with its pH) Cubbi 04:56, 8 May 2007 (UTC)

No merger plz

It should stay.

Actually, if you want real justification, the reason I looked in wikipedia for this particular answer is that you can count the number of strong acids or bases (under standard conditions) on two hands. Therefore as a seperate page, it is a comprehensive resource.

this is a plus for me, if I wanted to know about acids or bases in general, I would look in my chemistry textbook. k. —The preceding unsigned comment was added by 129.96.142.18 (talk • contribs) .

Undecided

I dont think that the pages should be merged, but that the strong bases page should be made more comprehensive. They are both useful, and I have used them and the Acid pages to help me with a chemistry project.

However, a merge would have benefits. If they were combined, then finding what you wanted may be easier.

I don't know.

Could be good, could be bad.

Probably useful, though.

Commander Bubble 11:12, 13 September 2006 (UTC)

decision time merge!

I am counting 4 editors in favor of merge, one against and one undecided, so unless there are objections the proposed merge will take place within 48 hours and try to keep merge discussion within one discussion please..V8rik 20:11, 29 September 2006 (UTC)

Sodium Hydroxide + Water

When NaOH is dissolved in water, doesn't it actually produce Na⁺ and H₃O₂^-?

actually it produces a hydrated sodium cation and a hydrated hydroxide anion, which are commonly written as Na+ and OH-. Or, if you want to be pedantic, as Na+(aq) and OH-(aq) Cubbi 16:11, 4 April 2007 (UTC)

doesn't that depend on the definition of acid-base chem you're working with?

Strong bases

The stronger the base, the smaller the pKb value. Therefore the claim that strong bases are those with pKb GREATER than 13 doesn't make sense. Perhaps you meant pH?

Ranking of strong hydroxide bases?

In the article, it states that KOH is stronger than CsOH. Is this true? I've heard that CsOH is the strongest hydroxide base. It readily dissolves glass, but KOH can't. Also, it's hard to believe that RbOH is weaker than LiOH. It seems like there is no trend in strength of the alkali hydroxides in this ranking.

BTW, tetramethylammonium hydroxide is also a strong hydroxide base. So you can add it if you wish. Warut 21:05, 29 November 2006 (UTC)

strength has to do with a base's equilibrium constant; a weak base goes back and forth ( BOH<->B+ + OH-) while a strong only goes 1 way (BOH --> B+ +OH-). or are you talking about pure concentrations?????

A strong base (or acid) is one that disassociates completely (or close enough that you can't tell otherwise). That means that CsOH is equal to NaOH is equal to KOH. Ba(OH)2 is stronger, as are any strong bases that have two hydroxides. N.B. Not everything with a OH attached is a strong base, for example Mg(OH)2 is a weak base (and fairly insoluable to boot). ^one/_zero 03:15, 25 July 2007 (UTC)

Then why is Ba(OH)₂ listed as weaker than KOH? Warut (talk) 11:14, 5 December 2007 (UTC)

I think we should drop any pretense of such a ranking's existence. If it exists, it is not widely known, and at any rate it would be fairly pointless. Also, there is the question of what relative strength means at all. In ranking acids, we use only the first dissociation, since subsequent dissociations change the pH very little. But here we cannot ignore the fact that a base like Ba(OH)₂ produces two moles of hydroxide ions. So we'd have to ask ourselves: Is one base stronger than another because it can raise the pH more at a fixed concentration, or because its first dissociation is more complete? And how meaningful would such a decision be anyway? Like I said, it's better not to try to rank at all. Bbi5291 (talk) 17:01, 24 October 2009 (UTC)

Strong AND weak?

Under Base Definitions: "Bases may also be weak bases such as ammonia" Then Neutralization of Acids: "Neutralizing acid spills with strong bases, such as lye or ammonia..." Yeah... I'll just change the latter, feel free to argue that ammonia is actually a strong base(about 1% of it is protonated, although don't check the ammonia article on that; it says the exact opposite and I've posted there as well) Lowe--81.233.253.191 12:25, 14 January 2007 (UTC)

Tasting a base

Acid solutions taste sour, even dilute solutions of weak acids such as acetic acid. Thus, I'd expect you can taste sodium bicarbonate to get the taste of a base. To my palate, the taste of baking soda is not bitter. I taste bitter when I taste alkaloids. My schooling used the term "brackish" to define the taste of a base. Perhaps, there's a better term. However, I'd like to see something other than "bitter" describing the taste of a base.

Chemperson 23:08, 25 April 2007 (UTC)

Strong bases taste bitter, from my experience. Cubbi 00:44, 26 April 2007 (UTC)

Baking soda is not a base, it is a salt (chemistry). --Chemicalinterest (talk) 00:39, 8 September 2010 (UTC)

Dissociation constant

I think the value of the dissociation constant is incorrect, well for 23°C anyway.

"The concentration, measured in molarity (M or moles per dm³), of the ions is indicated as [H₃O⁺] and [OH⁻]; their product is the dissociation constant of water with and has the value 10⁻⁷ M."

Should this not be 10⁻¹⁴ M, with [H₃O⁺] being 10⁻⁷ M, giving you a pH of -log 10⁻⁷ = 7.

Another Overtechnical Wikipedia Page

It's just plain confusing to read. Can someone who knows what this is about please make it easier to understand? —Preceding unsigned comment added by 75.20.200.74 (talk) 01:19, 20 November 2008 (UTC)

I personally think the page is quite clear. While I might be judging this article's standards by the little chemistry I know, I do not think we can clarify it further. Although, reading over the introduction to the article, it could use some cleanup, and a little merger of sentences rather than short fragmented sentences, with special conditions written in brackets, rather than specifically emphasized on. Do keep in mind that Wikipedia is not a Textbook, and thus can only present facts, not teach it. Aly89 (talk) 02:32, 20 November 2008 (UTC)

Some Confusion

An IP editor raised "Bases are different from alkalis" in the article. I have moved it here. Is this difference adequately dealt with? --Bduke (Discussion) 04:41, 9 April 2009 (UTC)

Etymology?

Is it known who came up with this word in chemistry? Why are bases called bases? Is the root meaning the same as in a baseball base or a space base, or is this "base" really a totally different word? www.etymonline.com doesn't have anything on this. Please include this info if you have it. -- 92.229.71.18 (talk) 14:47, 9 May 2010 (UTC)

See Definitions section, second paragraph re the 18th century French chemist Rouelle who introduced the word. Dirac66 (talk) 01:02, 8 September 2010 (UTC)

Apperently Rouelle is no longer mentioned in the article. Still, I'm sure etymology is important. This article (Jensen, William B. (2006). "The origin of the term "base"". The Journal of Chemical Education 83 (8): 1130. doi:10.1021/ed083p1130, http://www.che.uc.edu/Jensen/W.%20B.%20Jensen/Reprints/129.%20Base.pdf) would probably help, I'll add it to the article.95.25.177.242 (talk) 02:40, 22 June 2014 (UTC)

Thanks for pointing out that it was gone. I searched the Revision history and found that the paragraph on etymology was deleted on 8 Apr 2013, along with the rest of the Definitions section whose content is duplicated elsewhere in the article. In fact the source for this paragraph was the same paper by Jensen, so I have restored the paragraph to the Wiki article, and used your formatting for the reference for easier reader access to Jensen's paper. Dirac66 (talk) 03:17, 22 June 2014 (UTC)

Question

why do we use strong bases to clean? —Preceding unsigned comment added by 122.71.228.48 (talk) 12:44, 18 May 2010 (UTC)

They can dissolve hair and grease. --Chemicalinterest (talk) 00:40, 8 September 2010 (UTC)

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Definition

The definition of base at the beginning , is not so good , compared to the definition of acid. — Preceding unsigned comment added by Wholecube (talk • contribs) 14:58, 9 November 2017 (UTC)

Strong Base vs Superbase

Should "Very strong bases can even deprotonate very weakly acidic C–H groups in the absence of water." be moved from the strong base to the superbase section? --Robert Rossi (talk) 12:07, 1 December 2017 (UTC)

Merger proposal

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

The result of this discussion was withdrawn. Original nominator withdrew merge nomination. Discussion can continue in the new section below. Mdewman6 (talk) 08:24, 18 December 2021 (UTC)

---

SassyGamer483 proposes that Alkali should be merged into Base (chemistry). Sassygamer483, please state why you think the articles should be merged. Mdewman6 (talk) 02:45, 18 December 2021 (UTC)

Close the merger proposal. I just realised that alkalis and bases are different substances. All this text should be mentioned in both articles: 1. All alkalis are water-soluble bases and but all bases are not alkalis. 2. Alkalis are metal hydroxides and metal oxides of Group IA and Group IIA of the Periodic Table whereas bases are substances that neutralize acids to form salts and water. Examples of water-insoluble bases (that are not alkalis) are copper oxide, ferrous oxide, ferric oxide, zinc carbonate. SassyGamer483 (talk) 06:15, 18 December 2021 (UTC)

Active editors may add on to the text SassyGamer483 (talk) 06:17, 18 December 2021 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Adequate distinction between bases and alkalis needed

Both articles need more detailed distinction between bases and alkalis. I have made some already below, and active editors may add on to the text to make it detailed.

All alkalis are water-soluble bases and but all bases are not alkalis. 2. Alkalis are metal hydroxides and metal oxides of Group IA and Group IIA of the Periodic Table whereas bases are substances that neutralize acids to form salts and water. Examples of water-insoluble bases (that are not alkalis) include copper oxide, ferrous oxide, ferric oxide, zinc carbonate, etc. SassyGamer483 (talk) 06:25, 18 December 2021 (UTC)

Comment

I think there is a key error in the "Reactions between bases and water" section in this article: when bases react with water and take a proton, thus outcompeting the resulting hydroxide ions for that proton, that indicates that it is a stronger base, not weaker, and its equilibrium constant value should be larger, not smaller. The pKb value, however, would be smaller.

Above comment added by user 204.84.6.15 on 4 March 2022 (and then moved down to end of talk page)

Reply: The point is that for a weak base B in (pure) water, only a very small fraction of B molecules take a proton from water to become BH⁺. If only 1% of B is protonated to BH⁺, then B is indeed considered a weak base as the article says. Dirac66 (talk) 01:25, 27 March 2022 (UTC)