See explanation below.
Work Step by Step
Variation of ACID STRENGTH with Atomic Size: In a Period, atomic size decreases from left to right. And in a group, Atomic size increases from top to bottom. Now, as atomic size increases, the bond length also increases, and thus Bond strength decreases. As a result, As E becomes larger, the E—H bond becomes longer and weaker, so H+ comes off more easily. On the contrary, the smaller non-metals attract electrons more strongly in the polar bond by shifting the electron density away from H, thus making H_ more easily transferred to a water molecule to form H3O+.