Question

Among the following, the correct statements are: 
Statement I – Nature of Saline (Ionic) Hydrides
Statement II – Volatility of Saline Hydrides
Statement III – Nature of Electron-Precise Hydrides
Statement IV – Formula of Chromium Hydride

• A. I, III only
• B. II, IV only
• C. I, IV only
• D. III, IV only

Hint:

Saline hydrides are generally non-volatile due to strong ionic bonding. Electron-precise hydrides do not act as Lewis bases because they lack lone pairs.

Answer 1

The Correct Option is C

Step 1: Saline Hydrides Explained
Saline hydrides, also known as ionic hydrides, are compounds formed between hydrogen and alkali or alkaline earth metals, such as LiH, BeH₂, and MgH₂. They exhibit strong ionic bonding, although lighter examples like BeH₂ and MgH₂ display some covalent characteristics. Consequently, Statement I is accurate.
Step 2: Volatility of Saline Hydrides
Volatility is determined by the strength of intermolecular forces. Due to their robust ionic bonds, saline hydrides are non-volatile. Therefore, Statement II is inaccurate.
Step 3: Electron-Precise Hydrides and Lewis Basicity
Electron-precise hydrides, including CH₄ and SiH₄, possess sufficient valence electrons for covalent bond formation. They function not as Lewis bases because they lack the requisite lone pairs for donation. Thus, Statement III is inaccurate.
Step 4: Chromium Hydride Composition
Chromium forms a hydride with the chemical formula CrH. Accordingly, Statement IV is accurate.
Step 5: Identifying the Correct Option
The statements confirmed as correct are (I) and (IV). Therefore, the correct selection is (C).