Acid vs. Alkali — What's the Difference?

A substance with a pH less than 7 that donates protons.

A base that dissolves in water to form a solution with a pH greater than 7.

A chemical that turns blue litmus paper red.

A compound that releases hydroxide ions in a solution.

A corrosive substance that can react with metals.

A bitter-tasting, slippery substance often used in cleaning products.

A compound that increases the concentration of hydrogen ions in a solution.

In chemistry, an alkali (; from Arabic: القلوي‎ al-qaly "ashes of the saltwort") is a basic, ionic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water.

An acid is a molecule or ion capable of either donating a proton (i.e., hydrogen ion, H+), known as a Brønsted–Lowry acid, or, capable of forming a covalent bond with an electron pair, known as a Lewis acid.The first category of acids are the proton donors, or Brønsted–Lowry acids. In the special case of aqueous solutions, proton donors form the hydronium ion H3O+ and are known as Arrhenius acids.

A compound with particular chemical properties including turning litmus blue and neutralizing or effervescing with acids; typically, a caustic or corrosive substance of this kind such as lime or soda

A substance with particular chemical properties including turning litmus red, neutralizing alkalis, and dissolving some metals; typically, a corrosive or sour-tasting liquid of this kind.

A carbonate or hydroxide of an alkali metal, the aqueous solution of which is bitter, slippery, caustic, and characteristically basic in reactions.

A molecule or other species which can donate a proton or accept an electron pair in reactions.

Any of various soluble mineral salts found in natural water and arid soils.

The drug LSD

Alkali metal.

Containing acid or having the properties of an acid; having a pH of less than 7.

A substance having highly basic properties; a strong base.

Sharp-tasting or sour

(chemistry) One of a class of caustic bases, such as soda, soda ash, caustic soda, potash, ammonia, and lithia, whose distinguishing characteristics are dissolving in alcohol and water, uniting with oils and fats to form soap, neutralizing and forming salts with acids, turning to brown several vegetable yellows, and changing reddened litmus to blue.

(of rock, especially lava) containing a relatively high proportion of silica

(Western United States) Soluble mineral matter, other than common salt, contained in soils of natural waters.

Any of a class of substances whose aqueous solutions are characterized by a sour taste, the ability to turn blue litmus red, and the ability to react with bases and certain metals to form salts.

Soda ash; caustic soda, caustic potash, etc.

A substance that yields hydrogen ions when dissolved in water.

One of a class of caustic bases, such as soda, potash, ammonia, and lithia, whose distinguishing peculiarities are solubility in alcohol and water, uniting with oils and fats to form soap, neutralizing and forming salts with acids, turning to brown several vegetable yellows, and changing reddened litmus to blue.

A substance that can act as a proton donor.

Soluble mineral matter, other than common salt, contained in soils of natural waters.

A substance that can accept a pair of electrons to form a covalent bond.

Any of various water-soluble compounds capable of turning litmus blue and reacting with an acid to form a salt and water;

A substance having a sour taste.

A mixture of soluble salts found in arid soils and some bodies of water; detrimental to agriculture

The quality of being sarcastic, bitter, or scornful

A substance that turns red litmus paper blue.

(Slang) See LSD1.

A substance that neutralizes acids to form salts and water.

Of, relating to, or containing an acid.

Having a high concentration of acid.

Having the characteristics of an acid.

Having a pH of less than 7.

Having a relatively high concentration of hydrogen ions.

(Geology) Containing a large proportion of silica

Having a sour taste.

Biting, sarcastic, or scornful

Sour, sharp, or biting to the taste; tart; having the taste of vinegar.

(figuratively) Sour-tempered.

Of or pertaining to an acid; acidic.

(music) Denoting a musical genre that is a distortion (as if hallucinogenic) of an existing genre, as in acid house, acid jazz, acid rock.

A sour substance.

(chemistry)

Any compound which yields H+ ions (protons) when dissolved in water; an Arrhenius acid.

Any compound that easily donates protons to a base; a Brønsted acid.

Any compound that can accept a pair of electrons to form a covalent bond; a Lewis acid.

Any corrosive substance.

LSD, lysergic acid diethylamide.

Sour, sharp, or biting to the taste; tart; having the taste of vinegar: as, acid fruits or liquors. Also fig.: Sour-tempered.

Of or pertaining to an acid; as, acid reaction.

A sour substance.

One of a class of compounds, generally but not always distinguished by their sour taste, solubility in water, and reddening of vegetable blue or violet colors. They are also characterized by the power of destroying the distinctive properties of alkalies or bases, combining with them to form salts, at the same time losing their own peculiar properties. They all contain hydrogen, united with a more negative element or radical, either alone, or more generally with oxygen, and take their names from this negative element or radical. Those which contain no oxygen are sometimes called hydracids in distinction from the others which are called oxygen acids or oxacids.

Any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt

Street name for lysergic acid diethylamide

Harsh or corrosive in tone;

Containing acid;

A sour-tasting substance often found in fruits.

Acids have a pH less than 7 and donate protons, while alkalis have a pH greater than 7 and accept protons or donate hydroxide ions.

Acids can turn blue litmus paper red and usually taste sour.

Common alkalis include sodium hydroxide, potassium hydroxide, and baking soda.

Alkalis turn red litmus paper blue and typically feel slippery.

Acids taste sour due to the presence of hydrogen ions which stimulate sour taste receptors.

Alkalis feel slippery because they react with oils on the skin to form soap-like substances.

Yes, acids can be corrosive and cause burns or damage to materials.

Acids like vinegar and lemon juice are used for cooking and preserving food.

No, some alkalis can be very corrosive and harmful to skin and eyes.

Common acids include hydrochloric acid, sulfuric acid, and citric acid.

Alkalis like baking soda and ammonia are used for cleaning and deodorizing.

Acids help in digestion (stomach acid), while alkalis like bicarbonates help maintain pH balance in the blood.

They neutralize each other, forming water and a salt.

If not managed properly, alkalis can pollute water sources.

Acids can contribute to acid rain, which harms ecosystems.