TS EAMCET 4-Aug-2021 Shift 2 Question Paper

In f-block element, due to lanthanide contraction, the size of M3+ ions (i.e. Ce3+,Lu3+, Gd3+ ) decreases and thus, basic strength of their hydroxide also decreases. The order of size of given M3+ ions is Ce3+>Gd3+>Lu3+. Hence, Ce(OH)3 is the most basic hydroxide among all of these.
Lanthanide contraction ∝‌

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‌ basic strength ‌

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