Base (chemistry) - Revision history

Jmdonev at 19:20, 4 January 2019

2019-01-04T19:20:41Z

← Older revision		Revision as of 19:20, 4 January 2019
Line 4:		Line 4:
	<onlyinclude>A '''base''' or '''alkaline''' is any substance that will react with water to produce OH<sup>-</sup><ref name=libre>Chemistry LibreTexts. (July 11 2018). ''Overview of Acids and Bases'' [online], Available:https://chem.libretexts.org/Textbook_Maps/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Acid/Overview_of_Acids_and_Bases </ref> Generally, solutions of bases in water will have a [[pH]] greater than 7.</onlyinclude>		<onlyinclude>A '''base''' or '''alkaline''' is any substance that will react with water to produce OH<sup>-</sup><ref name=libre>Chemistry LibreTexts. (July 11 2018). ''Overview of Acids and Bases'' [online], Available:https://chem.libretexts.org/Textbook_Maps/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Acid/Overview_of_Acids_and_Bases </ref> Generally, solutions of bases in water will have a [[pH]] greater than 7.</onlyinclude>

	In water, there is always some H<sup>+</sup> and OH<sup>-</sup> [[ion]]s in solution due to the self-ionization of water. In basic solutions, there will be more OH<sup>-</sup> than H<sup>+</sup>. More concentrated bases will have more OH<sup>-</sup> in solution. Following the pH scale, a more basic solution - one with more OH<sup>-</sup> - will have a <em>higher</em> pH value. ~~</onlyinclude>~~[[Acid]]s can react with bases in a [[neutralization]] reaction, where the H<sup>+</sup> from the acid reacts with the OH<sup>-</sup> of the base to produce a solution with a lower OH<sup>-</sup> concentration - and a lower pH - than the original base solution.		In water, there is always some H<sup>+</sup> and OH<sup>-</sup> [[ion]]s in solution due to the self-ionization of water. In basic solutions, there will be more OH<sup>-</sup> than H<sup>+</sup>. More concentrated bases will have more OH<sup>-</sup> in solution. Following the pH scale, a more basic solution - one with more OH<sup>-</sup> - will have a <em>higher</em> pH value. [[Acid]]s can react with bases in a [[neutralization]] reaction, where the H<sup>+</sup> from the acid reacts with the OH<sup>-</sup> of the base to produce a solution with a lower OH<sup>-</sup> concentration - and a lower pH - than the original base solution.

	Most common inorganic bases are hydroxides (containing OH<sup>-</sup> in their composition), such as sodium hydroxide, NaOH, or calcium hydroxide, Ca(OH)<sub>2</sub>. However some [[organic molecule\|organic]] bases exist, such as ammonia-based molecules like amines, that do not contain OH<sup>-</sup> directly: any OH<sup>-</sup> in a solution of these molecules is formed from a reaction with water. <ref name=libre3>Chemistry LibreTexts. (July 11, 2018). ''Organic Acids and Organic Bases'' [online], Available: https://chem.libretexts.org/Textbook_Maps/Organic_Chemistry/Map%3A_Organic_Chemistry_(McMurry)/chapter_02%3A_Polar_Covalent_Bonds%3B_Acids_and_Bases/2.10_Organic_Acids_and_Organic_Bases#Ammonia_as_a_weak_base </ref>		Most common inorganic bases are hydroxides (containing OH<sup>-</sup> in their composition), such as sodium hydroxide, NaOH, or calcium hydroxide, Ca(OH)<sub>2</sub>. However some [[organic molecule\|organic]] bases exist, such as ammonia-based molecules like amines, that do not contain OH<sup>-</sup> directly: any OH<sup>-</sup> in a solution of these molecules is formed from a reaction with water. <ref name=libre3>Chemistry LibreTexts. (July 11, 2018). ''Organic Acids and Organic Bases'' [online], Available: https://chem.libretexts.org/Textbook_Maps/Organic_Chemistry/Map%3A_Organic_Chemistry_(McMurry)/chapter_02%3A_Polar_Covalent_Bonds%3B_Acids_and_Bases/2.10_Organic_Acids_and_Organic_Bases#Ammonia_as_a_weak_base </ref>

Jmdonev at 19:19, 4 January 2019

2019-01-04T19:19:53Z

← Older revision		Revision as of 19:19, 4 January 2019
Line 2:		Line 2:
	[[File:bleachs.JPG\|160px\|thumb\|Figure 1. Bleach has a pH of around 12-13.]]		[[File:bleachs.JPG\|160px\|thumb\|Figure 1. Bleach has a pH of around 12-13.]]

	<onlyinclude>A '''base''' or '''alkaline''' is any substance that will react with water to produce OH<sup>-</sup><ref name=libre>Chemistry LibreTexts. (July 11 2018). ''Overview of Acids and Bases'' [online], Available:https://chem.libretexts.org/Textbook_Maps/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Acid/Overview_of_Acids_and_Bases </ref> Generally, solutions of bases in water will have a [[pH]] greater than 7.		<onlyinclude>A '''base''' or '''alkaline''' is any substance that will react with water to produce OH<sup>-</sup><ref name=libre>Chemistry LibreTexts. (July 11 2018). ''Overview of Acids and Bases'' [online], Available:https://chem.libretexts.org/Textbook_Maps/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Acid/Overview_of_Acids_and_Bases </ref> Generally, solutions of bases in water will have a [[pH]] greater than 7.</onlyinclude>

	In water, there is always some H<sup>+</sup> and OH<sup>-</sup> [[ion]]s in solution due to the self-ionization of water. In basic solutions, there will be more OH<sup>-</sup> than H<sup>+</sup>. More concentrated bases will have more OH<sup>-</sup> in solution. Following the pH scale, a more basic solution - one with more OH<sup>-</sup> - will have a <em>higher</em> pH value. </onlyinclude>[[Acid]]s can react with bases in a [[neutralization]] reaction, where the H<sup>+</sup> from the acid reacts with the OH<sup>-</sup> of the base to produce a solution with a lower OH<sup>-</sup> concentration - and a lower pH - than the original base solution.		In water, there is always some H<sup>+</sup> and OH<sup>-</sup> [[ion]]s in solution due to the self-ionization of water. In basic solutions, there will be more OH<sup>-</sup> than H<sup>+</sup>. More concentrated bases will have more OH<sup>-</sup> in solution. Following the pH scale, a more basic solution - one with more OH<sup>-</sup> - will have a <em>higher</em> pH value. </onlyinclude>[[Acid]]s can react with bases in a [[neutralization]] reaction, where the H<sup>+</sup> from the acid reacts with the OH<sup>-</sup> of the base to produce a solution with a lower OH<sup>-</sup> concentration - and a lower pH - than the original base solution.

Jmdonev: 1 revision imported

2018-07-21T01:12:57Z

1 revision imported

← Older revision	Revision as of 01:12, 21 July 2018
(No difference)

Jmdonev at 02:04, 13 July 2018

2018-07-13T02:04:55Z

← Older revision		Revision as of 02:04, 13 July 2018
Line 1:		Line 1:
	[[Category:Done ~~2015~~-07-24]]		[[Category:Done 2018-07-20]]
	[[File:bleachs.JPG\|160px\|thumb\|Figure 1. Bleach has a pH of around 12-13.]]		[[File:bleachs.JPG\|160px\|thumb\|Figure 1. Bleach has a pH of around 12-13.]]

	<onlyinclude>A '''base''' or '''alkaline''' is ~~defined as~~ any substance with ~~a [[pH]] greater than 7. This means that the [[ion]] concentration of [[hydrogen]] (H<sup>+</sup>) is less than the concentration of hydroxide (~~OH<sup>-</sup>).</onlyinclude> A higher pH means a higher basicity, and thus a higher concentration of OH<sup>-</sup> ions in the solution. These types of substances exhibit distinct properties: they feel slippery and have a bitter taste when ingested.<ref name=~~ucd~~>~~UC Davis Chem Wiki~~. (July ~~8, 2015~~). ''~~Acid/Base Basics~~'' [~~Online~~], Available: ~~http~~://~~chemwiki~~.~~ucdavis~~.~~edu~~/~~Physical_Chemistry~~/Acids_and_Bases/Acid~~#Neutralization~~</ref>		<onlyinclude>A '''base''' or '''alkaline''' is any substance that will react with water to produce OH<sup>-</sup><ref name=libre>Chemistry LibreTexts. (July 11 2018). ''Overview of Acids and Bases'' [online], Available:https://chem.libretexts.org/Textbook_Maps/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Acid/Overview_of_Acids_and_Bases </ref> Generally, solutions of bases in water will have a [[pH]] greater than 7.

	~~When mixed with an~~ [[~~acid~~]], the pH ~~of the new~~ solution will ~~balance out towards the neutral~~ pH ~~of 7~~, ~~depending on~~ the ~~strength~~ of the ~~acid~~ and base. ~~This~~ is ~~known as neutralization~~.<ref name=~~ucd~~/>		In water, there is always some H<sup>+</sup> and OH<sup>-</sup> [[ion]]s in solution due to the self-ionization of water. In basic solutions, there will be more OH<sup>-</sup> than H<sup>+</sup>. More concentrated bases will have more OH<sup>-</sup> in solution. Following the pH scale, a more basic solution - one with more OH<sup>-</sup> - will have a <em>higher</em> pH value. </onlyinclude>[[Acid]]s can react with bases in a [[neutralization]] reaction, where the H<sup>+</sup> from the acid reacts with the OH<sup>-</sup> of the base to produce a solution with a lower OH<sup>-</sup> concentration - and a lower pH - than the original base solution.

			Most common inorganic bases are hydroxides (containing OH<sup>-</sup> in their composition), such as sodium hydroxide, NaOH, or calcium hydroxide, Ca(OH)<sub>2</sub>. However some [[organic molecule\|organic]] bases exist, such as ammonia-based molecules like amines, that do not contain OH<sup>-</sup> directly: any OH<sup>-</sup> in a solution of these molecules is formed from a reaction with water. <ref name=libre3>Chemistry LibreTexts. (July 11, 2018). ''Organic Acids and Organic Bases'' [online], Available: https://chem.libretexts.org/Textbook_Maps/Organic_Chemistry/Map%3A_Organic_Chemistry_(McMurry)/chapter_02%3A_Polar_Covalent_Bonds%3B_Acids_and_Bases/2.10_Organic_Acids_and_Organic_Bases#Ammonia_as_a_weak_base </ref>

	===Uses===		===Uses===

	~~Bases~~ have ~~many uses, alongside their~~ neutralizing ~~abilities for acidic substances~~, such as ~~when~~ [[~~acid rain~~]] ~~is neutralized~~ by ~~stones~~ and ~~minerals with a high pH~~. ~~Some uses include~~:		The ability of bases to [[neutralization\|neutralize]] acids is very useful, as many reactions and industrial processes have acidic waste products. Some examples of using bases to neutralizing unwanted acids:
			*[[Acid rain]] can be neutralized by basic minerals, such as limestone. (Limestone is mainly calcium carbonate.<ref name=geo>Geology.com. (July 11, 2018). ''Limestone'' [online], Available: https://geology.com/rocks/limestone.shtml</ref>)
			*[[Scrubber]]s used in [[power plant]]s use bases (e.g. calcium hydroxide) in order to reduce the release of [[sulfur oxides]] (a type of acidic [[pollutant]]) produced by the plant.
			*Antacids contain bases (most often calcium carbonate) that react with stomach acid in order to treat heartburn and indigestion. <ref name=libre2>Chemistry Libretexts. (July 11, 2018). ''Heartburn'' [online], Available: https://chem.libretexts.org/Textbook_Maps/General_Chemistry/Map%3A_A_Molecular_Approach_(Tro)/16%3A_Acids_and_Bases/16.01%3A_Heartburn</ref>

	*[[Scrubber]]s used in [[power plant]]s make use of ~~certain~~ bases ~~like Calcium hydroxide~~ in ~~order to chemically clean the [[sulfur oxides]] (a type of [[pollutant]]) produced by the plant.~~		Outside of neutralization, bases are also used in chemical reactions:
	*~~Antacids containing magnesium~~ hydroxide are ~~ingested in order~~ to ~~balance out~~ [~~[acid~~]~~]ity in the stomach in order to cure indigestion~~.
	*Sodium ~~hydroxide~~ is ~~used to make soaps~~, ~~while calcium hydroxide~~ is ~~used~~ to ~~make bleaching powder.~~		*Sodium hydroxide and potassium hydroxide are used to make soaps. <ref name=soap>Ogden Publications Inc. (July 11, 2018). ''Mother Earth Living: Honey and Beeswax Soap Recipe'' [online], Available: https://www.motherearthliving.com/health-and-wellness/beauty-recipes/honey-and-beeswax-soap-recipe-ze0z1506zdeb</ref>
	*Sodium ~~hydrogen carbonate~~ (baking soda) ~~has many applications~~.		*Sodium hypochlorite (NaOCl) is the main ingredient in laundry bleach. <ref name=bleach>Chlorox. (July 11, 2018). ''What is bleach?'' [online], Available: https://www.clorox.com/how-to/laundry-basics/bleach-101/bleach/ </ref>
			*Sodium bicarbonate (baking soda) is used to generate gases for leavening bread and baked goods, and in some fire extinguishers. <ref name=fire>Piper Fire Protection Inc. (July 11, 2018). ''Types of Fire Extinguishers and What They Do''. [online]. Available: http://www.piperfire.com/types-of-fire-extinguishers-and-what-they-do/</ref>

	[[File:pHacid.png\|800px\|thumb\|center\|Figure 2. Various acids and bases on the pH scale.<ref>Adapted from Energy: Its use and the Environment -- R. A. Hinrichs and M. Kleinbach, "Acid Rain," in ''Energy: Its Use and the Environment'', 5th ed. Toronto, Ont. Canada: Brooks/Cole, 2006, ch.8, sec.C, pp.252-256</ref>]]		[[File:pHacid.png\|800px\|thumb\|center\|Figure 2. Various acids and bases on the pH scale.<ref>Adapted from Energy: Its use and the Environment -- R. A. Hinrichs and M. Kleinbach, "Acid Rain," in ''Energy: Its Use and the Environment'', 5th ed. Toronto, Ont. Canada: Brooks/Cole, 2006, ch.8, sec.C, pp.252-256</ref>]]

	To learn more about acids and bases please see [http://~~chemwiki~~.~~ucdavis~~.edu/~~Physical_Chemistry~~/~~Acids_and_Bases UC Davis's chem wiki~~].		To learn more about acids and bases please see [https://chem.libretexts.org/Textbook_Maps/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Acid/Overview_of_Acids_and_Bases the Chemistry LibreText].

			==Phet Simulation==
			The [http://phet.colorado.edu/ University of Colorado] has graciously allowed us to use the following Phet simulation. Explore this simulation to see how the pH of acids and bases work.

			<html>
			<iframe src="https://phet.colorado.edu/sims/html/acid-base-solutions/latest/acid-base-solutions_en.html" width="800" height="600"></iframe>
			</html>

			==For Further Reading==
			*[[Acid]]
			*[[The pH scale]]
			*[[Chemical]]
			*[[Water]]
			*[[Acid rain]]
			*[[Water cycle]]
			*Or explore a [[Special:Random\|random page]]

			To learn more about acids and bases please see [https://chem.libretexts.org/Textbook_Maps/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Acids_and_Bases/Acid/Overview_of_Acids_and_Bases the Chemistry LibreText].
	==References==		==References==
	{{~~Reflist~~}}		{{reflist}}
	~~[[Category:Uploaded]]~~

J.williams: 1 revision imported

2015-08-26T21:30:47Z

1 revision imported

← Older revision	Revision as of 21:30, 26 August 2015
(No difference)

J.williams at 16:40, 12 August 2015

2015-08-12T16:40:35Z

New page

[[Category:Done 2015-07-24]]
[[File:bleachs.JPG|160px|thumb|Figure 1. Bleach has a pH of around 12-13.]]

<onlyinclude>A '''base''' or '''alkaline''' is defined as any substance with a [[pH]] greater than 7. This means that the [[ion]] concentration of [[hydrogen]] (H+) is less than the concentration of hydroxide (OH-).</onlyinclude> A higher pH means a higher basicity, and thus a higher concentration of OH- ions in the solution. These types of substances exhibit distinct properties: they feel slippery and have a bitter taste when ingested.<ref name=ucd>UC Davis Chem Wiki. (July 8, 2015). ''Acid/Base Basics'' [Online], Available: http://chemwiki.ucdavis.edu/Physical_Chemistry/Acids_and_Bases/Acid#Neutralization</ref>

When mixed with an [[acid]], the pH of the new solution will balance out towards the neutral pH of 7, depending on the strength of the acid and base. This is known as neutralization.<ref name=ucd/>

===Uses===

Bases have many uses, alongside their neutralizing abilities for acidic substances, such as when [[acid rain]] is neutralized by stones and minerals with a high pH. Some uses include:

*[[Scrubber]]s used in [[power plant]]s make use of certain bases like Calcium hydroxide in order to chemically clean the [[sulfur oxides]] (a type of [[pollutant]]) produced by the plant.
*Antacids containing magnesium hydroxide are ingested in order to balance out [[acid]]ity in the stomach in order to cure indigestion.
*Sodium hydroxide is used to make soaps, while calcium hydroxide is used to make bleaching powder.
*Sodium hydrogen carbonate (baking soda) has many applications.

[[File:pHacid.png|800px|thumb|center|Figure 2. Various acids and bases on the pH scale.<ref>Adapted from Energy: Its use and the Environment -- R. A. Hinrichs and M. Kleinbach, "Acid Rain," in ''Energy: Its Use and the Environment'', 5th ed. Toronto, Ont. Canada: Brooks/Cole, 2006, ch.8, sec.C, pp.252-256</ref>]]

To learn more about acids and bases please see [http://chemwiki.ucdavis.edu/Physical_Chemistry/Acids_and_Bases UC Davis's chem wiki].

==References==
{{Reflist}}
[[Category:Uploaded]]