Which of the following is a correct order of basicity?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. CsOH>KOH>NaOH>LiOH
The correct order of basicity among the alkali metal hydroxides is CsOH > KOH > NaOH > LiOH. This order is primarily due to the decreasing lattice energy and increasing ionic size of the alkali metals as one moves down the group in the periodic table. Cesium hydroxide (CsOH), being associated with the largest alkali metal ion, has the weakest lattice energy, making it the most basic. Conversely, lithium hydroxide (LiOH) has the highest lattice energy due to the small size of the lithium ion, resulting in lower basicity. Thus, larger ions result in stronger bases in this context.