1.
The types of bonds present in NH4Cl are:
a. ionic, covalent and coordinate
b. only ionic
c. ionic and covalent
d. covalent and coordinate
NH4Cl Bonds: Ionic, Covalent, Coordinate Covalent Explained
NH4Cl, or ammonium chloride, contains three types of bonds: ionic between NH4+ and Cl-, covalent bonds within the NH4+ ion, and one coordinate covalent bond. The correct answer is option a. ionic, covalent and coordinate. This structure arises from ammonia (NH3) reacting with HCl, forming the polyatomic ammonium cation and chloride anion.
Option Analysis
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a. ionic, covalent and coordinate: Correct. NH4Cl features an ionic bond due to electrostatic attraction between NH4+ (cation) and Cl- (anion). Inside NH4+, three N-H bonds are covalent (shared electron pairs), and the fourth is coordinate covalent (both electrons from nitrogen’s lone pair donated to H+).
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b. only ionic: Incorrect. While the overall compound is ionic, the NH4+ ion contains covalent and coordinate bonds, not just ionic attraction between ions.
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c. ionic and covalent: Incomplete. Ignores the coordinate covalent bond in NH4+, where nitrogen provides both electrons for one N-H bond.
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d. covalent and coordinate: Wrong. Excludes the primary ionic bond holding the NH4+ and Cl- ions together in the crystal lattice.
Bond Formation Breakdown
Ammonium chloride forms when NH3 accepts H+ from HCl:
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Nitrogen in NH3 has a lone pair, forming three covalent N-H bonds initially.
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The lone pair donates to H+, creating NH4+ with one coordinate bond (dative covalent).
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Cl gains the electron to become Cl-, enabling ionic bonding with NH4+.
Lewis structure: [N with four H, + charge] paired with [Cl with 8 electrons, – charge]. This confirms all three bond types, making NH4Cl a classic example in chemistry exams like CSIR NET.
