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What is the reason that HCL is a stronger acid than HF?
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+ Hydrochloric acid
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Laiba Athar
What is the reason that HCL is a stronger acid than HF?
HCl is a strong acid because it completely dissociates in water to give H⁺ and Cl⁻ ions.
However, HF is a weak acid. When HF releases H⁺ ion and F⁻ ions in aqueous solution, the H⁺ ion will form hydronium ion (H₃O⁺) with water molecule. Since F is very electronegative, the F⁻ ion would form strong hydrogen bonds with the H⁺ released, i.e. F⁻••••H⁺••••OH₂. This much lowers the activity of H₃O⁺ ions, leading to lowering of apparent concentration of H₃O⁺ ions. Besides, H-F bond is strong due to the short bond length, and thus much energy is needed to break bond. Hence, HF is a weak acid.
HCl is a strong acid because it completely dissociates in water to give H⁺ and Cl⁻ ions.
However, HF is a weak acid. When HF releases H⁺ ion and F⁻ ions in aqueous solution, the H⁺ ion will form hydronium ion (H₃O⁺) with water molecule. Since F is very electronegative, the F⁻ ion would form strong hydrogen bonds with the H⁺ released, i.e. F⁻••••H⁺••••OH₂. This much lowers the activity of H₃O⁺ ions, leading to lowering of apparent concentration of H₃O⁺ ions. Besides, H-F bond is strong due to the short bond length, and thus much energy is needed to break bond. Hence, HF is a weak acid.
Hydrogen bonds are very strong intermolecular bonds caused by the sharing of hydrogen ions between very electronegative atoms. For an acid to be strong, it has to dissociate to form as many hydrogen ions as possible. The hydrogen ions in hydrogen fluoride are attracted to the fluorine atoms by hydrogen bonds. Thus the hydrogen ions in hydrofluoric acid cannot be released fully. Hydrochloric acid, meanwhile, has no hydrogen bonds. Thus it can fully dissociate to form hydrogen ions and chloride ions.
Hydrogen bonds are very strong intermolecular bonds caused by the sharing of hydrogen ions between very electronegative atoms. For an acid to be strong, it has to dissociate to form as many hydrogen ions as possible. The hydrogen ions in hydrogen fluoride are attracted to the fluorine atoms by hydrogen bonds. Thus the hydrogen ions in hydrofluoric acid cannot be released fully. Hydrochloric acid, meanwhile, has no hydrogen bonds. Thus it can fully dissociate to form hydrogen ions and chloride ions.
HCl is a strong acid because it completely dissociates in water to give H⁺ and Cl⁻ ions.
However, HF is a weak acid. When HF releases H⁺ ion and F⁻ ions in aqueous solution, the H⁺ ion will form hydronium ion (H₃O⁺) with water molecule. Since F is very electronegative, the F⁻ ion would form strong hydrogen bonds with the H⁺ released, i.e. F⁻••••H⁺••••OH₂. This much lowers the activity of H₃O⁺ ions, leading to lowering of apparent concentration of H₃O⁺ ions. Besides, H-F bond is strong due to the short bond length, and thus much energy is needed to break bond. Hence, HF is a weak acid.
HCl is a strong acid because it completely dissociates in water to give H⁺ and Cl⁻ ions.
However, HF is a weak acid. When HF releases H⁺ ion and F⁻ ions in aqueous solution, the H⁺ ion will form hydronium ion (H₃O⁺) with water molecule. Since F is very electronegative, the F⁻ ion would form strong hydrogen bonds with the H⁺ released, i.e. F⁻••••H⁺••••OH₂. This much lowers the activity of H₃O⁺ ions, leading to lowering of apparent concentration of H₃O⁺ ions. Besides, H-F bond is strong due to the short bond length, and thus much energy is needed to break bond. Hence, HF is a weak acid.
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Hydrogen fluoride has hydrogen bonds.
Hydrogen bonds are very strong intermolecular bonds caused by the sharing of hydrogen ions between very electronegative atoms. For an acid to be strong, it has to dissociate to form as many hydrogen ions as possible. The hydrogen ions in hydrogen fluoride are attracted to the fluorine atoms by hydrogen bonds. Thus the hydrogen ions in hydrofluoric acid cannot be released fully. Hydrochloric acid, meanwhile, has no hydrogen bonds. Thus it can fully dissociate to form hydrogen ions and chloride ions.
—Gt. Yuhan Zhang (Proud A-level Chemistry student)
Hydrogen fluoride has hydrogen bonds.
Hydrogen bonds are very strong intermolecular bonds caused by the sharing of hydrogen ions between very electronegative atoms. For an acid to be strong, it has to dissociate to form as many hydrogen ions as possible. The hydrogen ions in hydrogen fluoride are attracted to the fluorine atoms by hydrogen bonds. Thus the hydrogen ions in hydrofluoric acid cannot be released fully. Hydrochloric acid, meanwhile, has no hydrogen bonds. Thus it can fully dissociate to form hydrogen ions and chloride ions.
—Gt. Yuhan Zhang (Proud A-level Chemistry student)
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