Difference Between Hydrochloric Acid and Sulfuric Acid

Main Difference

The main difference between hydrochloric acid and sulfuric acid is that the hydrochloric acid is the type of mineral acid that contains only one proton in the compound, whereas the sulfuric acid is the type of mineral acid that contains only two protons in the compound.

Hydrochloric Acid vs. Sulfuric Acid

Hydrochloric acid is the acid that is known as the monobasic, whereas the sulfuric acid is the acid that is also known as the dibasic. Hydrochloric acid contains only one proton; on the other hand, sulfuric acid contains only two protons. Hydrochloric acid is a weaker acid than the sulfuric acid; on the flip side, sulfuric acid is the stronger acid than the hydrochloric acid.

The formula mass of hydrochloric acid is 36.5 gram per mole while the formula mass of sulfuric acid is 98 gram per mole. Hydrochloric acid is also known as monoprotic; on the other hand, sulfuric acid has another name, diprotic. Hydrochloric acid gives one proton in one molecule in the solution, whereas the sulfuric acid gives two protons in one molecule in the solution.

Hydrochloric acid does not contain hydroxyl group in the molecule; on the flip side, sulfuric acid contains two hydroxyl groups in the molecule. The chemical formula of hydrochloric acid is HCl; on the other hand, the chemical formula of sulfuric acid is H2SO4. Hydrochloric acid has weak chemical properties, whereas the sulfuric acid has strong chemical properties.

Hydrochloric acid acts as a weak reducing agent, whereas the sulfuric acid acts as a strong oxidizing agent. The pH of the hydrochloric acid is greater than the pH of sulfuric acid while the sulfuric acid has a pH little less than the pH of the hydrochloric acid. Hydrochloric acid has one hydrogen and one chlorine atom in the composition of the formula, on the contrary, sulfuric acid has two hydrogens, four oxygen and one sulfur atom in the composition of the formula.

Hydrochloric acid has a gaseous form at room temperature; on the other hand, sulfuric acid is a liquid at room temperature. In hydrochloric acid, the chlorine atom is the main nucleophile, on the opposite, in sulfuric acid Sulphur atom is the main nucleophile. The pKa of the hydrochloric acid is greater than that of sulfuric acid, whereas the pKa of sulfuric acid is less than that of hydrochloric acid.

The catalytic power of hydrochloric acid is less prominent than that of sulfuric acid, whereas the catalytic power of sulfuric acid is greater than that of hydrochloric acid. The ionization of hydrochloric acid in water occurs in one step; on the flip side, the ionization of sulfuric acid in water occurs in two steps.

Comparison Chart

Hydrochloric AcidSulfuric Acid
The hydrochloric acid is the type of mineral acid that contains only one proton in the compound.The sulfuric acid is the acid that is also known as the dibasic.
Ionization Steps
Only in one step as it contains only one stepOnly in two steps as it contains two-step
Catalytic Ability
Less prominent catalytic abilityMore prominent ability
pH
High pHLow pH
pKa
lowhigh
Physical Nature
Gas at room temperatureOily liquid at room temperature
Nucleophilic Atom
Main Chlorine atomMain Sulphur atom
Chemical Formula
HClH2SO4
Chemical Composition
Hydrogen and chlorine atomsHydrogen, oxygen and Sulphur atoms
Oxidizing/Reducing
Reducing agentOxidizing agent
Molar Mass
36.5 gram per mole98 gram per mole
-OH Groups
AbsentTwo hydroxyl groups
Numbers of Protons
One proton-monobasic acidTwo protons-dibasic acid
Strength of Acid
Weak acidStrong acid

What is Hydrochloric Acid?

The hydrochloric acid is the acid that has its ability to donate one proton in the aqueous solution. It has only one step in the ionization process; that’s because it is also known as the monobasic type of acid. The hydrochloric acid also acts as a nucleophile in some chemical reactions as it contains a chlorine atom in the compound. It also has some catalytic power in some reactions.

The chemical formula of hydrochloric acid is HCl as it has hydrogen and chlorine atom in the chemical composition. The hydrochloric acid is a weak acid that is present in gaseous form at room temperature. -7 is the pKa of the hydrochloric acid in the chemistry. But it has a high pKa value. The hydrochloric acid is the acid that is usually known as a weak reducing agent.

It can easily oxidize the compounds by donating the protons. The formula mass of hydrochloric acid is 36.5 gram per mole. The hydroxyl groups are absent in the chemical formula of the hydrochloric acid. This acid is usually used in a salt analysis to find the relative groups of the atoms. The hydrochloric acid reacts with the strong base to form the relative salt and water.

Applications

  • Purification of salts
  • Regulation of acidity of the solution
  • To control the pH of the medicinal products
  • To control the pH of foods
  • To control the pH of intake water
  • To neutralize the steam of waste
  • To neutralize the alkaline containing the substances
  • To manufacture glue
  • For bleaching products

What is Sulfuric Acid?

The sulfuric acid is the acid that has its ability to donate two protons in the aqueous solution. It has only two-step in the ionization process that’s because it is also known as the dibasic type of acid. The sulfuric also acts as a nucleophile in some chemical reactions as it contains Sulphur atom in the compound.

It also has more prominent catalytic power in reactions of chemistry. The chemical formula of sulfuric acid is H2SO4 as it has hydrogens, oxygen, and Sulphur atoms in the chemical composition. The sulfuric acid is the strong acid and has low pKa value that is present in the liquid form at the room temperature.

The sulfuric acid is the acid that is usually known as the strong oxidizing agent. 98 gram per mole refers as the formula mass of it. It also contains two hydroxyl groups in the chemical formula.

Applications

  • To manufacture chemicals
  • To make HCl, nitric acid, salts
  • To manufacture dyes, explosives, detergents, and drugs.

Key Differences

  1. Hydrochloric acid is generally the monobasic acid; on the other hand, the sulfuric acid is generally the dibasic acid.
  2. The chemical formula of hydrochloric acid is HCl; on the other hand, the chemical formula of sulfuric acid is H2SO4.
  3. The process of dissociation of hydrochloric acid completes in one step; on the flip side, the process of dissociation of sulfuric acid completes in two steps.
  4. Hydrochloric acid is the type of the weaker acid; on the flip side, sulfuric acid is the type of the stronger acid.
  5. The value of pH of the hydrochloric acid is greater than the pH of sulfuric acid while the sulfuric acid has a pH little less than the pH of the hydrochloric acid.
  6. The formula mass of the hydrochloric acid is 36.5 gram per mole while formula mass the of sulfuric acid is 98 gram per mole.
  7. Hydrochloric acid is generally the example of monoprotic acid; on the other hand, sulfuric acid is generally the example of a diprotic acid.
  8. No hydroxyl group is present in the structural formula of hydrochloric acid while two hydroxyl groups are present in the structural formula of sulfuric acid.
  9. The chemical properties of hydrochloric acid are very weak; on the other hand, the chemical properties of sulfuric acid are very strong.
  10. The chemical composition of hydrochloric acid includes hydrogen and chlorine atoms while the chemical composition of sulfuric acid includes hydrogen, sulfur, and oxygen atoms.
  11. The hydrochloric acid gives one proton to one molecule in the solution, whereas the sulfuric acid gives two protons to one molecule in the solution.
  12. The physical nature of hydrochloric acid is gaseous; on the other hand, the physical nature of sulfuric acid is liquid.
  13. The hydrochloric acid includes in the category of weaker reducing agent, whereas the sulfuric acid includes in the category of the stronger oxidizing agent.
  14. In hydrochloric acid, the main nucleophile is the chlorine atom, on the opposite, in sulfuric acid, the main nucleophile is the sulfur atom.
  15. The value of pKa of the hydrochloric acid is generally greater than the pKa value of sulfuric acid, on the flip side the value of pKa of sulfuric acid is generally less than the pKa value of hydrochloric acid.
  16. The hydrochloric acid holds only one hydrogen ion; on the other hand, the sulfuric acid holds only two hydrogen ions.
  17. The ability to catalyze the reaction of hydrochloric acid is very less; on the other hand, the ability to catalyze the reaction of sulfuric acid is very high.

Conclusion

The above discussion concludes that both the hydrochloric acid and sulfuric acid are types of mineral acids. The hydrochloric acid is an acid of containing one proton, whereas the sulfuric acid is an acid of containing two protons.

Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss

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