Photo:1
Photo:2
Photo:3
Photo:4
Photo:1 Photo:2 Photo:3 Photo:4 |
| Etymology | |
| 2>
The word "alkali" is derived from Arabic al qalīy (or al kali),[1] meaning the calcined ashes (see calcination), referring to the original source of alkaline substances. A water-extract of burned plant ashes, called potash and composed mostly of potassium carbonate, was mildly basic. After heating this substance with calcium hydroxide (slaked lime), a far more strongly basic substance known as caustic potash (potassium hydroxide) was produced. Caustic potash was traditionally used in conjunction with animal fats to produce soft soaps, one of the caustic processes that rendered soaps from fats in the process of saponification, known since antiquity. Plant potash lent the name to the element potassium, which was first derived from caustic potash, and also gave potassium its chemical symbol K (cf German Kalium), which ultimately derives from alkali.
[edit] Tags:Arabic,Basic,Water,Potash,Calcium Hydroxide,Potassium Hydroxide,Soaps,Saponification,Potassium,Kalium, | |
| Common properties | |
| 2>
Alkalis are all Arrhenius bases, which form hydroxide ions (OH-) when dissolved in water. Common properties of alkaline aqueous solutions include:
Moderately concentrated solutions (over 10−3 M) have a pH of 7.1 or greater. This means that they will turn phenolphthalein from colorless to pink.
Concentrated solutions are caustic (causing chemical burns).
Alkaline solutions are slippery or soapy to the touch, due to the saponification of the fatty acids on the surface of the skin.
Alkalis are normally water soluble, although some like barium carbonate are only soluble when reacting with an acidic aqueous solution.
Acids and alkalis are measured on a pH scale
Turns Universal Indicator Blue-Dark Purple.
[edit] Tags:Base,Ph,Arrhenius,Solutions,Phenolphthalein,Water Soluble,Arrhenius Base, | |
| Difference between alkali and base | |
| 2>
The terms "base" and "alkali" are often used interchangeably, particularly outside of a scientific context.
There are various definitions for alkali. Alkali is often defined as a subset of base. However, two subsets are commonly chosen.
A basic salt of an alkali metal or alkaline earth metal[2] (This includes Mg(OH)2 but excludes NH3.)
Any base that is water-soluble and forms hydroxide ions[3][4][5] or the solution of a base in water.[6] (This excludes Mg(OH)2 but includes NH3.)
The second subset of base is also called an Arrhenius base.
[edit] Tags:Salt, | |
| Salts | |
| 2>
Most basic salts are alkali salts, of which common examples are:
sodium hydroxide (often called "caustic soda")
potassium hydroxide (commonly called "caustic potash")
lye (generic term, for either of the previous two, or even for a mixture)
calcium carbonate (sometimes called "free lime" or "limewater")
magnesium hydroxide is an example of an atypical alkali since it has low solubility in water (although the dissolved portion is considered a strong base due to complete dissociation of its ions).
[edit] Tags:Sodium Hydroxide,Lye,Calcium Carbonate, | |
| Alkaline soil | |
| 2>
Soil with a pH value higher than 7.3 is normally referred to as alkaline. This soil property can occur naturally, due to the presence of alkali salts. Although some plants do prefer slightly basic soil (including vegetables like cabbage and fodder like buffalograss), most plants prefer a mildly acidic soil (pH between 6.0 and 6.8), and alkaline soils can cause problems.
[edit] Tags:Cabbage,Buffalograss, | |
| Alkali lakes | |
| 2>
In alkali lakes (a type of salt lake), evaporation concentrates the naturally occurring alkali salts, often forming a crust of mildly basic salt across a large area.
Examples of alkali lakes:
Alkali Lake, British Columbia, Canada Referenced in feature movies X-Men II and III
Alkali Lake (Oregon), Oregon, United States
Baldwin Lake (San Bernardino County, California)
Mono lake, California, United States
Redberry Lake, Saskatchewan, Canada
Summer Lake, Oregon, United States
Tramping Lake, Saskatchewan, Canada
Lake Magadi, Kenya
Lake Turkana, Kenya (the largest alkali lake in the world)
[edit] Tags:British Columbia,Oregon,United States,Baldwin Lake (san Bernardino County, California),Mono Lake,California,Redberry Lake, Saskatchewan,Canada,Summer Lake,Tramping Lake, Saskatchewan,Lake Magadi,Lake Turkana, | |
| References | |
| 2>
^ Chambers's encyclopaedia: a dictionary of universal knowledge, Volume 1. J.B. Lippincott & Co. 1888. p. 148.
^ http://dictionary.reference.com/search?q=alkali
^ http://www.tiscali.co.uk/reference/encyclopaedia/hutchinson/m0029936.html
^ http://www.thefreedictionary.com/alkali
^ http://www.wahyan.edu.hk/paulsir/handout/form4/4-05_Characteriscs_of_alkali.pdf
^ http://www.krysstal.com/acidbase.html
Retrieved from "http://en.wikipedia.org/w/index.php?title=Alkali&oldid=476207970"
Categories: Inorganic chemistryArabic words and phrasesHidden categories: Articles needing additional references from June 2008All articles needing additional references
Personal tools
Log in / create account
Namespaces
Article
Talk
Variants
Views
Read
Edit
View history
Actions
Search
Navigation
Main page
Contents
Featured content
Current events
Random article
Donate to Wikipedia
Interaction
Help
About Wikipedia
Community portal
Recent changes
Contact Wikipedia
Toolbox
What links here
Related changes
Upload file
Special pages
Permanent link
Cite this page
Print/export
Create a bookDownload as PDFPrintable version
Languages
العربية
Беларуская (тарашкевіца)
Català
Deutsch
Eesti
Español
Esperanto
Euskara
فارسی
Français
한국어
Ido
Interlingua
עברית
ಕನ್ನಡ
ქართული
Қазақша
Latina
Latviešu
Lietuvių
Magyar
日本語
Norsk (bokmål)
Novial
O'zbek
پنجابی
Polski
Русский
Shqip
Simple English
తెలుగు
ไทย
Türkçe
Українська
اردو
Vahcuengh
中文
This page was last modified on 11 February 2012 at 00:33.
Text is available under the Creative Commons Attribution-ShareAlike License;
additional terms may apply.
See Terms of use for details.
Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.Contact us
Privacy policy
About Wikipedia
Disclaimers
Mobile view
if ( window.isMSIE55 ) fixalpha();
if ( window.mediaWiki ) {
mw.loader.load(["mediawiki.user", "mediawiki.util", "mediawiki.page.ready", "mediawiki.legacy.wikibits", "mediawiki.legacy.ajax", "mediawiki.legacy.mwsuggest", "ext.gadget.wmfFR2011Style", "ext.vector.collapsibleNav", "ext.vector.collapsibleTabs", "ext.vector.editWarning", "ext.vector.simpleSearch", "ext.UserBuckets", "ext.articleFeedback.startup", "ext.articleFeedbackv5.startup", "ext.markAsHelpful"]);
}
if ( window.mediaWiki ) {
mw.user.options.set({"ccmeonemails":0,"cols":80,"date":"default","diffonly":0,"disablemail":0,"disablesuggest":0,"editfont":"default","editondblclick":0,"editsection":1,"editsectiononrightclick":0,"enotifminoredits":0,"enotifrevealaddr":0,"enotifusertalkpages":1,"enotifwatchlistpages":0,"extendwatchlist":0,"externaldiff":0,"externaleditor":0,"fancysig":0,"forceeditsummary":0,"gender":"unknown","hideminor":0,"hidepatrolled":0,"highlightbroken":1,"imagesize":2,"justify":0,"math":1,"minordefault":0,"newpageshidepatrolled":0,"nocache":0,"noconvertlink":0,"norollbackdiff":0,"numberheadings":0,"previewonfirst":0,"previewontop":1,"quickbar":5,"rcdays":7,"rclimit":50,"rememberpassword":0,"rows":25,"searchlimit":20,"showhiddencats":false,"showjumplinks":1,"shownumberswatching":1,"showtoc":1,"showtoolbar":1,"skin":"vector","stubthreshold":0,"thumbsize":4,"underline":2,"uselivepreview":0,"usenewrc":0,"watchcreations":1,"watchdefault":0,"watchdeletion":0,"watchlistdays":3,"watchlisthideanons":0,
"watchlisthidebots":0,"watchlisthideliu":0,"watchlisthideminor":0,"watchlisthideown":0,"watchlisthidepatrolled":0,"watchmoves":0,"wllimit":250,"flaggedrevssimpleui":1,"flaggedrevsstable":0,"flaggedrevseditdiffs":true,"flaggedrevsviewdiffs":false,"vector-simplesearch":1,"useeditwarning":1,"vector-collapsiblenav":1,"usebetatoolbar":1,"usebetatoolbar-cgd":1,"wikilove-enabled":1,"variant":"en","language":"en","searchNs0":true,"searchNs1":false,"searchNs2":false,"searchNs3":false,"searchNs4":false,"searchNs5":false,"searchNs6":false,"searchNs7":false,"searchNs8":false,"searchNs9":false,"searchNs10":false,"searchNs11":false,"searchNs12":false,"searchNs13":false,"searchNs14":false,"searchNs15":false,"searchNs100":false,"searchNs101":false,"searchNs108":false,"searchNs109":false,"gadget-wmfFR2011Style":1});;mw.user.tokens.set({"editToken":"+\\","watchToken":false});;mw.loader.state({"user.options":"ready","user.tokens":"ready"});
/* cache key: enwiki:resourceloader:filter:minify-js:4:b41a86ec4e0fe8329bc3ce917e792339 */
}
Tags:/,English,Categories,Inorganic Chemistry,Arabic Words And Phrases,Articles Needing Additional References From June 2008,All Articles Needing Additional References,Main Page, | |
zote monety click here click here click here click here |