Alkali vs. Alkaline: What's the Difference?
Edited by Aimie Carlson || By Janet White || Published on November 29, 2023
Alkali refers to a base that dissolves in water, whereas alkaline describes a solution with a pH greater than 7.
Key Differences
Alkali substances are specific bases that can dissolve in water, forming hydroxide ions. In contrast, alkaline refers to the property of a solution that contains dissolved alkali substances, resulting in a pH above 7.
Alkalis are often metal hydroxides like sodium hydroxide, exhibiting distinctive properties such as soapiness in solution. Alkaline, however, is an adjective describing any solution that exhibits basicity, like sea water, which becomes alkaline due to dissolved minerals.
The term alkali also encompasses elements in the alkali metal group of the periodic table, known for their reactivity with water. Alkaline conditions imply the presence of these or other basic substances in a solution, influencing its chemical behavior.
Alkali substances can be naturally occurring, such as potassium hydroxide in wood ash. Alkaline solutions, like many natural waters, owe their character to the presence of dissolved alkali substances.
Usage of alkali is often in industrial and chemical contexts for reactions, cleaning, or manufacturing. Alkaline environments are significant in biology and environmental science, impacting organism survival and chemical reactions.
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Comparison Chart
Definition
A base that dissolves in water
A solution with a pH above 7
Usage in Grammar
Used as a noun
Used as an adjective
Examples
Sodium hydroxide, potassium hydroxide
Alkaline water, alkaline soil
Context of Use
Chemistry, specifically bases
Describing pH levels of solutions
Relation to Water
Reacts with water to form solutions
Refers to the pH nature of the solution
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Alkali and Alkaline Definitions
Alkali
A substance forming hydroxide ions (OH-) in water.
Lye, a strong alkali, is used in drain cleaners.
Alkaline
Capable of neutralizing acids.
Alkaline substances are used to balance the pH in swimming pools.
Alkali
A basic, ionic salt of an alkali metal.
Baking soda contains an alkali that neutralizes acids.
Alkaline
Opposite of acidic in terms of pH scale.
The alkaline solution turned the litmus paper blue.
Alkali
A water-soluble base.
Sodium hydroxide is a common alkali used in soap making.
Alkaline
A solution where hydroxide ions (OH-) predominate.
The alkaline nature of the soap helps in effective cleaning.
Alkali
A member of the alkali metals group.
Potassium, an alkali metal, reacts vigorously with water.
Alkaline
Characterized by the presence of an alkali.
Alkaline water is often consumed for its health benefits.
Alkali
A compound that neutralizes acids.
The alkali in antacids helps relieve stomach acidity.
Alkaline
Of, relating to, or containing an alkali.
Alkali
A carbonate or hydroxide of an alkali metal, the aqueous solution of which is bitter, slippery, caustic, and characteristically basic in reactions.
Alkaline
Having a pH greater than 7.
Alkali
Any of various soluble mineral salts found in natural water and arid soils.
Alkaline
Having a relatively low concentration of hydrogen ions.
Alkaline
Of or relating to a common disposable battery made of zinc and manganese dioxide.
Alkaline
Of, or relating to an alkali, one of a class of caustic bases.
Alkaline
(chemistry) Having a pH greater than 7.
Alkaline
An alkaline battery.
Alkaline
Of or pertaining to an alkali or to alkalies; having the properties of an alkali.
Alkaline
Relating to or containing an alkali; having a pH greater than 7;
Alkaline soils derived from chalk or limestone
FAQs
Are all bases alkalis?
No, only those that dissolve in water.
How do alkalis react with acids?
They neutralize each other.
What is an alkali?
A substance that forms hydroxide ions in water.
What does alkaline mean?
Describing a solution with a pH greater than 7.
Is seawater alkaline?
Yes, typically it is slightly alkaline.
Can an alkali be a gas?
No, alkalis are ionic and not gaseous.
Do alkalis have a pH value?
Yes, alkalis have a pH above 7.
Can drinking water be alkaline?
Yes, some drinking water is naturally alkaline.
Can an acid be alkaline?
No, acids are not alkaline.
Can alkalis conduct electricity?
Yes, when dissolved in water.
Is an alkaline diet beneficial?
Some believe it helps balance body pH.
Are alkaline solutions always safe?
No, some can be corrosive.
Are alkalis found in food?
Yes, many foods contain natural alkalis.
Does an alkaline pH affect health?
Yes, both high and low pH can impact health.
What makes a solution alkaline?
The presence of dissolved alkali substances.
Is soap an alkali?
Yes, soap contains alkali substances.
What’s an example of an alkaline environment?
A baking soda solution.
Are all alkali metals alkalis?
Yes, when they react with water.
Can soil be alkaline?
Yes, soil pH can be alkaline.
Do alkalis have a taste?
Yes, they often taste bitter.
About Author
Written by
Janet WhiteJanet White has been an esteemed writer and blogger for Difference Wiki. Holding a Master's degree in Science and Medical Journalism from the prestigious Boston University, she has consistently demonstrated her expertise and passion for her field. When she's not immersed in her work, Janet relishes her time exercising, delving into a good book, and cherishing moments with friends and family.
Edited by
Aimie CarlsonAimie Carlson, holding a master's degree in English literature, is a fervent English language enthusiast. She lends her writing talents to Difference Wiki, a prominent website that specializes in comparisons, offering readers insightful analyses that both captivate and inform.