Home > Community > In alkali metals down the group basicity increase so why NAOH is more basic than KOH?
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+ Inorganic chemistry
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Natalie Feldman

In alkali metals down the group basicity increase so why NAOH is more basic than KOH?

Asad Hussain  Follow

How do the elements of group 2A differ from alkali metals?

The chief differences are:
They are harder and denser; they are less reactive (though still very reactive in absolute terms); they show a +2 valence instead of +1.

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Barry Austern  Follow

It's depending upon hydration enthalpy if hydration enthalpy is greater than lattice enthalpy nitrates soluble in water.

If not substance don't soluble in water.

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Anunley117  Follow

Ammonia. It’s composed of two nonmetals, hydrogen and nitrogen.

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Caro A  Follow

Technically there is no basicity for bases it is acidity.

I think you mean basic character.

Basic character increases down the group because many metallic characters like electropositivity, increases down the group.

Atomic radius too increases down the group making electronic transfer easier.

Ionisation enthalpy decreases down the group having favouring effect.

As a combined effect, going down the group first makes preparing the base itself easier and also gives us a more polar molecule of the base so it is easier for the base to dissociate and be more basic in nature.

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Nuel Rosson  Follow

When the group 1 metals react with water they form hydrogen, the metal cations and hydroxide ions. The production of OH- ions increases the ph thus creating alkaline conditions which is what I assume they derive their name from.

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Crow72  Follow

Most basic is koh and least is LIOH its bcoz

Of faijans rule as OH- is smaller ions and Li is too small which makes it more covalent therefore it cant produce oH- completely which tends to make it less basic also its polarising power is more. Whereas in KOh due to a big size diffrence and less polarizing powerit forms ionic bond more comfortabily and is most basic.

I think it is most simple reason u can remember…

And don’t forget to upvote .so i can get that u got it

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Christopher Brennan  Follow

The alkali metals are so called because upon reaction with water they generate free hydroxide; therefore high pH solution. I have no idea what is meant by the “three types of alkali”

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Aminat Aregbe  Follow

It isn’t.

A nice summary of what is known about these bases and the rest of the alkali metal hydroxides can be found at:

Is LiOH a weaker base than NaOH?

(and covers LiOH, NaOH, KOH, RbOH, and CsOH). Bottom line is that the order of basicity is:

CsOH > RbOH > KOH > NaOH > LiOH

A rationale for this order is based on the relative electronegativity of the cations. The order of basicity appears to be inversely related to the electronegativity. Thus the more electropositive the more the cation may associate with the OH-, making it less available to act as a base.

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Bill Hawkins  Follow

They both do and can do serious damage.

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BWAMBALE JORAM  Follow

In bulk form and at ordinary temperatures and pressures, osmium metal does resist attack by all acids and alkalis, including potassium hydroxide.

However, in finely powdered form, osmium reacts with oxygen at elevated temperatures (200–300°C) to produce osmium tetroxide (OsO[math]_{4}[/math]).

Osmium tetroxide is water soluble and will react with strong bases such as potassium hydroxide to form osmates;-

2KOH + OsO[math]_{4}[/math] → 2K[math]^{+}[/math] + OsO[math]_{4}[/math](OH)[math]^{-2}_{2}[/math]

Osmium is not amphoteric.

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David Rosen  Follow

The alkali metals have a high electropositivity meaning that they readily lose their single valence electron in order to obey the octet rule

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