- No. i. What is difference between Arrhenius base and Bronsted-Lowry base?
Answer. Arrhenius base is a substance which dissociates in aqueous solution to give hydroxyl ions. The substances like NaOH, KOH, NH4OH, Ca (OH)2 etc. are Arrhenius bases.
A Bronsted-Lowry base is a substance that can accept a proton (H+) from another substance. For example NH3 is a Bronsted-Lowry base.
- No. ii. What do you mean by neutralization reaction according to Arrhenius acid-base concept?
Answer. According to Arrhenius concept give H+ ions in water while bases give OH– ions in water. So, the neutralization reaction is formation of water along with salt. For example, HC1 is an acid and
NaOH is a base. They form salt and water such as;
HCl(aq) + NaOH(aq) NaCl(aq) + H2O(aq)
Q.No .iii. Prove that water is amphoteric specie.
Answer. A substance that can behave as an acid as well as a base is called amphoteric specie. For example, H2O behaves as amphoteric specie. According to Bronsted Lowry concept H2O behaves as a base because it accepts a proton (H+) when it reacts with HC1.
HCl(aq) + H2O (l) H3O+(aq) + CI–(aq)
On the other hand, H2O behaves as an acid because it donates a proton (H+) when it reacts with NH3
H2O(1) + NH3(aq) NH4+(aq) + OH–(aq)