
$HCl$ is gas but $HF$ is a low boiling liquid. This is because
A. H−F bond is strong
B. H−F bond is weak
C. Molecules aggregate because of hydrogen bonding
D. $HF$ is a weak acid
Answer
161.1k+ views
Hint: Halogen hydrides are covalent compounds. Therefore both hydrogen chloride and hydrogen fluoride are covalent compounds. But owing to the small size and very high electronegativity of fluorine it can form other bonds as well.
Complete Step by Step Answer:
Hydrogen chloride is formed due to the reaction of hydrogen atom and chlorine atom. Hydrogen atoms contain only one electron in its valence shell and chlorine atom also contains one electron less from noble gas configuration in its valence shell, so hydrogen and chlorine atoms share their electrons and form a covalent bond between them. Thus it exists as a gas.
Hydrogen fluoride has a covalent bond between hydrogen atom and fluorine atom. Due to the high electronegativity difference between $F$ and $H$, $HF$ can form hydrogen bonds and this bond is the strongest bond among all hydrogen halides. Thus due to formation of hydrogen bonding hydrogen fluoride exists as a liquid.
Thus the correct option is C.
Note: The reactivity of the halogens increases from iodine to fluorine. Thus chlorine is less reactive than fluorine. Due to high reactivity hydrogen fluoride is more acidic than hydrogen chloride.
Complete Step by Step Answer:
Hydrogen chloride is formed due to the reaction of hydrogen atom and chlorine atom. Hydrogen atoms contain only one electron in its valence shell and chlorine atom also contains one electron less from noble gas configuration in its valence shell, so hydrogen and chlorine atoms share their electrons and form a covalent bond between them. Thus it exists as a gas.
Hydrogen fluoride has a covalent bond between hydrogen atom and fluorine atom. Due to the high electronegativity difference between $F$ and $H$, $HF$ can form hydrogen bonds and this bond is the strongest bond among all hydrogen halides. Thus due to formation of hydrogen bonding hydrogen fluoride exists as a liquid.
Thus the correct option is C.
Note: The reactivity of the halogens increases from iodine to fluorine. Thus chlorine is less reactive than fluorine. Due to high reactivity hydrogen fluoride is more acidic than hydrogen chloride.
Recently Updated Pages
JEE Main 2021 July 25 Shift 1 Question Paper with Answer Key

JEE Main 2021 July 22 Shift 2 Question Paper with Answer Key

JEE Main Mock Test Series Class 12 Chemistry for FREE

Classification of Drugs Based on Pharmacological Effect, Drug Action

JEE Electricity and Magnetism Important Concepts and Tips for Exam Preparation

JEE Energetics Important Concepts and Tips for Exam Preparation

Trending doubts
JEE Main 2025 Session 2: Application Form (Out), Exam Dates (Released), Eligibility, & More

JEE Main 2025: Derivation of Equation of Trajectory in Physics

Electric Field Due to Uniformly Charged Ring for JEE Main 2025 - Formula and Derivation

Displacement-Time Graph and Velocity-Time Graph for JEE

JEE Main 2026 Syllabus PDF - Download Paper 1 and 2 Syllabus by NTA

JEE Main Eligibility Criteria 2025

Other Pages
JEE Advanced Marks vs Ranks 2025: Understanding Category-wise Qualifying Marks and Previous Year Cut-offs

NCERT Solutions for Class 12 Chemistry Chapter 1 Solutions

JEE Advanced 2025: Dates, Registration, Syllabus, Eligibility Criteria and More

NCERT Solutions for Class 12 Chemistry Chapter 2 Electrochemistry

NCERT Solutions for Class 12 Chemistry Chapter 6 Haloalkanes and Haloarenes

Solutions Class 12 Notes: CBSE Chemistry Chapter 1
