Arrhenius and bronstedlowry? (1 Viewer)

[lolmb]

In the arrhenius theory, acids IONISE to produce H+ ions in aqueous solution which then react with water molecules to produce hydronium H3O+.

In the bronsted lowry theory, do acids ionise? since they are described to 'donate protons'. is this still ionisation of the molecule in aqueous solution?

thanks

 

[zhertec]

In Arrhenius's theory, he believed that an acid was a molecule that is able to ionise in an aqueous solution to produce H+ ions, while a base is a molecule that is able to dissociate to produce OH- ions.

While the bronsted-lowry theory defines acid as proton donators and bases as proton acceptors, and yes it implies that the molecule ionises. But the difference/advantage of bronsted-lowry's definition is that it is not limited to aqueous solutions, and can be applied to gaseous reactions and neutralisation reactions involving carbonates.

The concept of hydronium ions was way after Arhennius (dunno about bronsted though), but when he implied that acids produced H+ ions, he was still referring to hydronium ions.

 

[Ekman]

In Arrhenius's theory, he believed that an acid was a molecule that is able to ionise in an aqueous solution to produce H+ ions, while a base is a molecule that is able to dissociate to produce OH- ions.

While the bronsted-lowry theory defines acid as proton donators and bases as proton acceptors, and yes it implies that the molecule ionises. But the difference/advantage of bronsted-lowry's definition is that it is not limited to aqueous solutions, and can be applied to gaseous reactions and neutralisation reactions involving carbonates.

The concept of hydronium ions was way after Arhennius (dunno about bronsted though), but when he implied that acids produced H+ ions, he was still referring to hydronium ions.

Just a little to add on that, Arrhenius's theory also had some limitations, such as Arrhenius couldn't explain why NH3 was base (since he defined all bases to have a OH function group at the end of the molecule), nor could he explain about acid and base strength since not all neutralization reactions produced a solution with a pH 7 ( take acetic acid and sodium hydroxide, the solution at the end is considered basic since sodium hydroxide is a strong base and acetic acid is a weak acid). However Bronsted-Lowry's theory of proton donors being acids and proton acceptors being bases, was able to explain everything about acids and bases that zhertec said above.