Answer
Bronsted acids are compounds that can donate one proton (a $H^+$ ion), and bronsted bases are compounds that can receive one proton.
- Example:
$HNO_2(aq)+ H_2O(l) \lt--\gt N{O_2}^-(aq) + H_3O^+(aq)$
Work Step by Step
This information about bronsted acids and bases can be found in any textbook or in the internet.
- In that example:
$HNO_2$ is the acid on the forward (left to right) reaction, because it gives one proton to water ($H_2O$).
${NO_2}^-$ is the base on the reverse (right to left) reaction, because it receives one $H^+$ from the $H_3O^+$, producing the acid $HNO_2$
This is a example of conjugate pair, because $N{O_2}^-$ is the result when $HNO_2$ acts like an acid, and vice versa.
