How do Sodium Sulfate and Hydrochloric Acid react?

Learn everything related to sodium sulfate and water reactions and when this sulfate salt is introduced in a corrosive acid like HCl.

Introduction:

Let’s review all the chemical entities involved in the following reactions; the first one is water which is the universal solvent, is ionic, and can act as both acidic and basic. The second one is sodium sulfate, which is a sulfate salt of sodium commonly extracted from Glauber's salt, its hydrated mineral found in nature. The last one is hydrochloric acid HCl which is a well-known corrosive oxidizing agent with various uses in the current industry.

Reaction of sodium sulfate and water:

Sodium sulfate is highly soluble in water and readily dissociates in its respective ions when introduced in a polar solvent, which is water in this case. There is no chemical activity leading to different products as these ions just stay in the solution and don’t undergo further chemical change.

Na₂SO₄ + H₂O → 2Na⁺ + SO₄^²⁻ 

You can observe the above reaction where the sodium sulfates don’t react with water to produce hydronium ions (H3O⁺) or hydroxide ions (OH⁻) as one would expect. Instead, it just sits there as it dissociates ions in the solution.

Reaction of Sodium Sulfate and Sulphuric Acid:

When these two are allowed to react with each other, they combine in a reversible fashion i.e. the products of this reaction may again react with each other to form HCl. Under standard conditions, this reaction is stated as:

2NaCl + H₂SO₄ → Na₂SO₄ + 2HCl

And when a reverse reaction occurs, the equation becomes:

Na₂SO₄ + 2HCl ⇌ 2NaCl + H₂SO₄

Note that in the first reaction, two moles of sodium chloride react with one mole of sulfuric acid to produce one mole of sodium sulfate and two moles of hydrochloric acid.

It is worth mentioning that the second reaction (reversed reaction) occurs to a limited extent and depends on various factors including the concentration of HCl used with Na₂SO₄, temperature, and presence of other ions in this solution.

Applications of NaSO₄ Solubility:

Sodium sulfate is very soluble in water. The solution of sodium sulfate and water has many industrial applications including its role in water treatment procedures, for industrial production of chemicals like sodium sulfide, sodium carbonate, etc., and during industrial processes of paper, and textiles. It is also used as a refining agent during glass production.

Thanks to its high solubility in ionic solvents, it is pretty useful during the production of powdered detergents where it increases the floating properties of the detergent. Moreover, it is used as a filler and fire retardant during the production of gypsum board (drywall). It is also heavily used in laboratory settings for various purposes e.g., as a precipitating agent and to dehydrate organic solvents.

is NaSO₄ soluble in Organic Solvents as well?

Due to the polar nature of sodium sulfate, it shows strong solubility in solvents with ionic compounds such as water and poses many applications. Organic compounds, it is sparingly soluble because of the clash of nature between the two entities.

This sulfate can be mixed with some organic solvents where it can dissolve to a certain and limited extent but due to weak electrostatic interactions, this solublity is also not stable leading to the settling down of this sulfate. It has a strong affinity with water molecules thanks to its strong interactions between sodium sulfate and water molecules.  

In general, this sulfate loves to take protons from strong acids like hydrochloric acid or sulfuric acid. By reacting with them, it readily forms soluble sodium salts (like sodium chloride in the above example).

Conclusion:

We can conclude that sodium sulfate and hydrochloric acid react in a reversible reaction forming sodium salt (common salt) along with sulfuric acid which can react again to reverse the reaction. However, this reversing reaction depends on different factors. Both sodium sulfate and water are highly soluble and offer significant benefits in several industries.