what are alkali bases?

Question

where can they be found
what is the safety needed

Answer 1

In chemistry, an alkali (from Arabic: al-qaly القالي) is a specific type of base, 'because an alkali is a base which is soluble in water' formed as a carbonate, hydroxide or other basic (pH greater than 7) ionic salt of an alkali metal or alkali earth metal element. The word alkali or the adjective alkaline are frequently used to refer to all bases, since most common bases are alkalis, although strictly speaking this is inaccurate. An Alkali is a base which will dissolve in water without causing a precipitate, however the solution could become saturated to give a false reading, but if a base in a small amount will dissolve in water without forming a precipitate, it is an Alkali. Therefore all alkalis are bases, but not all bases are alkali, as not all bases dissolve into water.

Alkalis are all Arrhenius bases and share many properties with other chemicals in this group (Arrhenius bases form hydroxide ions when dissolved in water). Common properties of alkaline solutions include:

All alkalis have a pH greater than seven and hence can be detected with litmus paper (litmus will turn blue on contact with an alkali).
Most alkalis have a pH of 10 or greater. This means that they will turn phenolphthalein from colorless to pink.
Caustic (causing chemical burns).
Alkaline solutions are slippery or soapy to the touch (due to the caustic reaction dissolving the surface of the skin and fingerprint).
Alkalis normally form aqueous solutions (although some like barium carbonate are only soluble when reacting with an acidic aqueous solution).
The terms "base" and "alkali" are often used interchangeably, since most common bases are alkalis. It is common to speak of "measuring the alkalinity of soil" when what is actually meant is the measurement of the pH (base property). Similarly, bases which are not alkalis, such as ammonia, are sometimes erroneously referred to as alkaline.

Note that not all or even most salts formed by alkali metals are alkaline; this designation applies only to those salts which are basic.

While most electropositive metal oxides are basic, only the soluble alkali metal and alkali earth metal oxides can be correctly called alkalis.

This definition of an alkali as a basic salt of an alkali metal or alkali earth metal does appear to be the most common, based on dictionary definitions , however conflicting definitions of the term alkali do exist. These include:

Any base that is water soluble . This is more accurately called an Arrhenius base.
The solution of a base in water.


Most basic salts are alkali salts, of which common examples are:

sodium hydroxide (common name caustic soda)
potassium hydroxide (potash lye)
lye (generic term, for either of the previous two, or even for a mixture)
sodium carbonate (soda ash)
potassium carbonate (potash)
Soil with a pH above 7.4 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 cabbage family vegetables and buffalograss), most plants prefer a mildly acidic soil (pH between 6.0 and 6.8), and high pH levels can cause a problem.

In alkali lakes (a type of salt lake), evaporation concentrates the naturally occurring alkali salts. When the lake evaporates completely, this forms a crust of mildly basic salt across a large area often called an alkali flat.

Examples of alkali lakes:

Redberry Lake, lake titikaka Saskatchewan, Canada.
Tramping Lake, Saskatchewan, Canada.
Great Salt Lake, Utah
In cities, cement or concrete rubble left in soil as landfill can raise pH.

The word "alkali" is derived from Arabic al qalīy = "the calcined ashes", referring to the original source of alkaline substance. Ashes were used in conjunction with animal fat to produce soap, a process known as saponification.

Answer 2

The terms "base" and "alkali" are often used interchangeably, since most common bases are alkalis. It is common to speak of "measuring the alkalinity of soil" when what is actually meant is the measurement of the pH (base property). Similarly, bases which are not alkalis, such as ammonia, are sometimes erroneously referred to as alkaline.

Note that not all or even most salts formed by alkali metals are alkaline; this designation applies only to those salts which are basic.

While most electropositive metal oxides are basic, only the soluble alkali metal and alkali earth metal oxides can be correctly called alkalis.

This definition of an alkali as a basic salt of an alkali metal or alkali earth metal does appear to be the most common, based on dictionary definitions [1][2], however conflicting definitions of the term alkali do exist. These include:

Any base that is water soluble [3][4]. This is more accurately called an Arrhenius base.
The solution of a base in water [5].

Answer 3

It's a base. Made of an alkali. Try Alkali Lake, from X-Men 2 & 3.

Answer 4

In chemistry, an alkali (from Arabic: al-qaly القالي) refers to an aqueous solution with a pH greater than 7. These tend to be formed from a carbonate, hydroxide or other basic ionic salt of an alkali metal or alkali earth metal element. The word alkali or the adjective alkaline are frequently used to refer to all bases, since most common bases are alkalis, although strictly speaking this is inaccurate. An alkali is a base which will dissolve in water without forming a precipitate. However, not all bases are water-soluble. Therefore all alkalis are bases, but not all bases are alkali.

Alkali Properties
* Most alkalis have a pH of 10 or greater, as measured by a pH meter or indicator solution. (See phenolphthalein.)
* Alkalis tend to be Caustic.
* Alkaline solutions are slippery or soapy to the touch, due to the caustic reaction dissolving the surface of the skin and fingerprint.
* Alkalis normally form aqueous solutions.

Confusion between base and alkali
The terms "base" and "alkali" are often used interchangeably, since most common bases are alkalis. It is common to speak of "measuring the alkalinity of soil" when what is actually meant is the measurement of the pH (base property). Similarly, bases which are not alkalis, such as ammonia, are sometimes erroneously referred to as alkaline.


While most electropositive metal oxides are basic, only the soluble alkali metal and alkali earth metal oxides can be correctly called alkalis.

This definition of an alkali as a basic salt of an alkali metal or alkali earth metal does appear to be the most common, based on dictionary definitions, and , however conflicting definitions of the term alkali do exist. These include:

* Any base that is water soluble. This is more accurately called an Arrhenius base.
* The solution of a base in water.

Alkali salts/sugars
Most basic salts are alkali salts, of which common examples are:

* sodium hydroxide (common name caustic soda)
* potassium hydroxide (potash lye)
* lye (generic term, for either of the previous two, or even for a mixture)
* sodium carbonate (soda ash)
* potassium carbonate (potash)

Alkaline soil
Soil with a pH above 7.4 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 cabbage family vegetables and buffalograss), most plants prefer a mildly acidic soil (pH between 6.0 and 6.8), and high pH levels can cause a problem.

In alkali lakes, (a type of salt lake), evaporation concentrates the naturally occurring alkali salts. When the lake evaporates completely, this forms a crust of mildly basic salt across a large area often called an alkali flat.

Examples of alkali lakes:

* Redberry Lake, Saskatchewan, Canada.
* Tramping Lake, Saskatchewan, Canada.
* Great Salt Lake, Utah

In cities, cement or concrete rubble left in soil as landfill can raise pH.

Etymology
The word "alkali" is derived from Arabic al qalīy = "the calcined ashes", referring to the original source of alkaline substance. Ashes were used in conjunction with animal fat to produce soap, a process known as saponification.

Application
Due to the increasing problem of water pollution and the health-concern related to the pH balance in human body, a Japanese manufacturer, Matsushita Electric Industrial Co., Ltd. has developed electric alkaline ionizers, which are complex, electric water filtering and water-ionizing systems under the brandname Panasonic.[6] According to the company, the filtration system has a "built-in electrolysis system generating alkaline water or weak acidic water". It is based on the belief & researches that weakly acidic water is good for skin-care and alkaline water is good for human consumption.

Answer 5

See.. By different concepts: A substance which can ionize to give OH ions is a base (Arrhenius); A substance which accepts H+ is a base (Bronsted-Lowry); A substance which accepts a pair of electrons is a base (Lewis). Any substance which falls into anyone or more than one of these definitions is a base. An alkali is a special type of base which is soluble in water. Every base is not an alkali. see whether you can understand these statements:- "EVERY ALKALI IS A BASE BUT EVERY BASE IS NOT AN ALKALI" "EVERY ARRHENIUS BASE IS AN ALKALI" Thus you can see that you cannot say that base doesnt dissolve in water. It is just that we have a special name for bases which dissolve in water to give OH ions: alkali. A base may or may not give OH in water or even may or may not be soluble in water, but an alkali always has both these properties. Ca(OH)2, NaOH, Ba(OH)2 are base as well as alkali but NH3 is only a base (Bronsted) not alkali. The main thing is that a base which is soluable in water is an alkali whereas a base which is not soluable in water is not an alkali. it can be said that alkali is a subset of bases.

Answer 6

"alkali" and "base" are two words which dasically mean the same thing.

In chemistry, they are opposite in reaction to acids. One donates a proton in chemical reactions whilst the other accepts a proton in these reactions. With one accepting and the other donating, a reaction between the two occures freely and a sult plus water is formed.

As with acids, you have a range of strengths. In simple terms, you take the same precautions with alcalis as you would with acids.

Answer 7

Anything which attaches itself to hydrogen ions H+
Common ones are hydroxyl (from NaOH for example).
OH- + H+ = H2O
Also ammonia NH3

NH3 + H+ = NH4+ (ammonium ion)

Strong alkalis can cause serious skin damage so goggles and spatulas are sensible.