Methylamine shows up as colorless gas and has a fishy, ammoniacal odor having actually the chemical formula CH3NH2. That is a derivative the ammonia however one hydrogen atom of ammonia is being replaced by a methyl group(CH3). 

 In this article, us will comment on Is CH3NH2 acid or base? Is it solid or weak? that conjugate acid-base pairs, etc.

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So, Is CH3NH2 an mountain or base? CH3NH2 is a basic in nature together when dissolved in one aqueous solution, that accepts the H+ ion native a water molecule and produces hydroxide ions (OH–) that correspondingly show its simple nature. 

Name that MoleculeMethylamine
Chemical formulaCH3NH2
Conjugate acid


NatureWeak base
Base dissociation constant (Kb)4.7 × 10-4

A base is characterized as a proton acceptor or lone pair donor. When CH3NH2 dissolves in water, it will certainly accept the H+ ion from the water and also gets converted into conjugate acid(CH3NH3+) and produce hydroxide ions(OH–).

⇒ CH3​NH2​ + H2​O ⇌ CH3​NH3+​ + OH−

The production of hydroxide ions on dissolving in one aqueous solution shows the straightforward nature of CH3NH2.

Theoretically, we have actually two essential acid-base theories to know whether CH3NH2 is acid or base.

(a). Arrhenius theory

(b). Bronsted-Lowry theory

(1). Arrhenius theory: 

According come Arrhenius theory, the link is claimed to it is in Arrhenius base when it to produce OH– ion through ionization or with dissociation in water and increases the concentration the OH– ion in an aqueous solution. (first definition)

Or a link is stated to be Arrhenius base when substance includes at least one unit of OH– in the chemical formula and produces OH– ion in water. (second definition)

Clearly, as soon as CH3NH2 is liquified in one aqueous equipment it accepts the proton and also produces OH– ion, and from the allude of an initial Arrhenius definition, CH3NH2 will act together Arrhenius base as the is maybe to boost the concentration that OH- in the final solution.


However, if girlfriend consider, second definition that Arrhenius base then CH3NH2 will not act together Arrhenius base due to the fact that it no contain any OH– in its chemistry formula.

(2). Bronsted-Lowry concept: 

According to the Bronsted-Lowry concept, a link is claimed to be base as soon as it accepts the proton from various other compounds and forms the conjugate acid. Or you have the right to say proton agree compounds are classified as Bronsted-Lowry base.

Take an instance to understand whether CH3NH2 basic or acid according to the Bronsted-lowry theory-

Consider the reaction that CH3NH2 with HCl


According come the over reaction, once CH3NH2 reacts through a solid acid(HCl), climate it will certainly accept the one proton from HCl and also itself it s okay converted right into conjugate acid(CH3NH3+), hence, according to the above definition, CH3NH2 will act together Bronsted-Lowry base.

Is CH3NH2 solid base or weak base?

To recognize whether CH3NH2 is a strong base or weak, girlfriend must understand the simple difference between a strong base or a weak base.

Strong base: A link is a solid base when it totally dissociates in an aqueous solution and also liberates a huge number of hydroxide ions. All moles that the strong base dissociate right into hydroxide ion(OH–) and no component remains undissociated into the solution.

Example: sodium hydroxide(NaOH), Barium hydroxide (Ba(OH)2), Calcium hydroxide (Ca(OH)2), Lithium hydroxide (LiOH), Potassium hydroxide (KOH), etc.

 Also, Read:–

Weak base: A compound is a weak base when it partly or not completely dissociate in one aqueous solution. It method only some components of the weak base dissociates in the solution to develop OH– ion yet some parts remain undissociated inside the solution.

Example- Ammonia hydroxide (NH4OH), Ammonia (NH3), etc.

 Also, Read:–

So, Is Methylamine (CH3NH2) a strong base or weak base? CH3NH2 is considered a weak base because when the is dissolved in an aqueous solution then no all the molecules of that react v water to yield OH– ions, very few molecules the CH3NH2 react v water molecule ions and produce OH– ion in the solution. 

And the quantity of OH– created in an aqueous equipment is really low as compared to the number of CH3NH2 moles we liquified in the solution.


As presented in the figure, once CH3NH2 is liquified in water, that accepts the hydrogen ion from the water molecule and also produces 2 ions(CH3NH3+ and also OH–) however the ion(CH3NH3+) is not stable in one alkaline environment, that keeps breaking right into CH3NH2 and H+.

⇒ CH3NH3+ ⇔ CH3NH2 + H+

Hence, no all the CH3NH2 molecules react v water ions and produce OH– ions, most of them stay together, only, a few molecules do interact with water, therefore, CH3NH2 is taken into consideration a weak base in nature.

Let’s know why CH3NH2 acts together the weak base with the aid of the dissociation consistent value concept.

⇒ If the value of the dissociation continuous of acid is better than 1 (Ka > 1), then the nature that the compound is a strong acid.

If Ka b >1, then the nature the the link is a strong base.

If Kb b) because that CH3NH2 is 4.7 × 10-4 that’s method lower 보다 recommended value for the strong base, hence, CH3NH2 is a weak basic in nature.

Here’s the list of some usual acids and bases with their strength.


Also check:- How come tell if the mountain or base is solid or weak?

⇒ Lewis base → lone pair donator

Now CH3NH2 acts together lewis’s base due to the fact that the main nitrogen atom has two lone pairs of electrons and it is always ready to provide up the lone pair of electron to an additional compound as it is very less electronegative in nature.

Let’s understand it through the aid of an example-


The electrons in the hydrogen-chlorine bonds attracted towards the chloride ion since of the high electronegativity leaving hydrogen slightly positive and also chlorine negative.

The lone pair ~ above the nitrogen of CH3NH2 molecule attracted in the direction of hydrogen atom in HCl molecule.

As it ideologies it, the electrons in the hydrogen-chlorine bond room repelled still more towards the chlorine.

Eventually, a co-ordinate shortcut is formed in between the nitrogen and the hydrogen, and also the chlorine breaks away as a chloride ion.

The entirety HCl molecule acts together Lewis mountain as it accept the lone pair from nitrogen atom, and in this procedure it breaks up.

So, HCl accepts the lone pair that the electron, therefore, it is Lewis acid and also CH3NH2 donates the lone pair of the electron, therefore, the is Lewis base.

In technological terms, Compounds distinguished from each various other by a single proton(H+) are stated to it is in Conjugate acid-base pairs.

In straightforward terms, once the proton is gotten rid of from parent acid then the compound is developed which is referred to as the conjugate basic of that acid and also when the proton is included to the parental base climate the compound is created which is called conjugate acid of the base.

Concept of Conjugate acid-base pair-


A an extremely weak acid develops the strong conjugate base.A very weak base forms strong conjugate acid.A very strong acid forms the weak conjugate base.A very strong base develops weak conjugate acid.

⇒ very weak way it doesn’t act as mountain or basic when dissolved in one aqueous solution.

⇒ Very solid means, acid or basic ionizes 100% when liquified in an aqueous solution.

So, what is the conjugate mountain of CH3NH2? As we discussed earlier, CH3NH2 is a weak base, hence, it will kind a conjugate mountain by including one proton to itself.


As you watch in the over reaction, CH3NH2 is a weak base and we recognize a weak base always forms a conjugate acid(not necessarily the strong one).

So, CH3NH3+ is the conjugate mountain of CH3NH2.

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Is CH3NH2 an mountain or base? CH3NH2 is considered as a base in nature due to the fact that the nitrogen atom consists of one lone pair which have the right to be used to accept the proton, hence, this leader to the formation of CH3NH3+ and also OH– once it is dissolved in water. The visibility of OH– in the aqueous solution results in pH increasing and also this makes the aqueous systems of CH3NH2 basic in nature.Methylamine (CH3NH2) is thought about a weak basic because not all the molecules of that react with water ions and produce OH– ions, most of them continue to be together, only, a couple of molecules do communicate with water, Therefore, the amount of OH– ions created in an aqueous equipment is really low as compared to the number of CH3NH2 moles we liquified in the solution.The basic dissociation constant value because that CH3NH2 is approximately 4.7 × 10-4 i m sorry is much less than 1 and that mirrors its weak basic nature.The conjugate acid of CH3NH2 is Methylammonium ion (CH3NH3+)