Question

Identify the correct statement

• A. $ \text{Yb}^{2+} $ is an oxidant
• B. $ \text{Lu}^{3+} $ is paramagnetic
• C. $ \text{CrO} $ is basic
• D. Brass is an alloy of Cu, Sn

Hint:

Remember the properties of lanthanide ions and the nature of metal oxides based on oxidation states. Know the composition of common alloys.

Answer 1

The Correct Option is C

To identify the correct statement among the given options, let's analyze each:

1. $ \text{Yb}^{2+} $ is an oxidant:

   $ \text{Yb}^{2+} $ is actually a reductant. Rare earth elements like Ytterbium can be present in +2 oxidation state and tend to get oxidized to +3. Hence, this statement is incorrect.

2. $ \text{Lu}^{3+} $ is paramagnetic:

   $ \text{Lu}^{3+} $ has the electronic configuration of [Xe]4f¹⁴5d⁰6s⁰. As it has no unpaired electrons, $ \text{Lu}^{3+} $ is diamagnetic, not paramagnetic. Therefore, this statement is incorrect.

3. $ \text{CrO} $ is basic:

   .$ \text{CrO} $ (Chromium(II) oxide) is a basic oxide. Basic oxides typically react with acids to form salt and water. Hence, this statement is correct.

4. Brass is an alloy of Cu, Sn:

   Brass is actually an alloy of copper (Cu) and zinc (Zn), not tin (Sn). Bronze is an alloy of copper and tin. Therefore, this statement is incorrect.

Conclusively, the correct statement is that $ \text{CrO} $ is basic.