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Consider the following

Which statements are properties of an acid? Statement 1: React with ammonium sulfate to form ammonia. Statement 2: Red litmus turns blue.

Obviously stataement 2 is false. However, I don't seem to understand statement 1. From my understanding, ammonium sulfate is a salt, meaning there shouldn't even be a reaction between an acid and ammonium sulfate. However, ammonium sulfate does react with a base. Ammonium sulfate is a neutral salt, so why does it even react with a base?

Since ammonium sulfate does react with a base, it is making me suspect that there is a reaction between ammonium sulfate and an acid. So what is this reaction mechanism? Why does it occur?

Please clarfiy the respective reactions between ammonium sulfate with a base or acid.

1 Answer

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Final answer:

Acids generally do not react with ammonium sulfate to form ammonia, as Statement 1 suggests; rather, it is the ammonium ions in solution that can slightly react with water to potentially form ammonia. Statement 2 is incorrect because acids turn blue litmus red, not blue; bases are responsible for turning red litmus paper blue.

Step-by-step explanation:

Regarding the properties of an acid: Statement 1 posits that acids react with ammonium sulfate to form ammonia. This reaction is not typically characteristic of acids, as ammonium sulfate is generally considered to be a neutral salt. However, it's important to understand that when dissolved in water, ammonium sulfate dissociates into ammonium ions (NH4+) and sulfate ions (SO42-).

The ammonium ion is the conjugate acid of ammonia and can undergo a slight reaction with water, producing hydronium ions (H3O+) and free ammonia (NH3). Thus, while direct reaction of acids with ammonium sulfate to form ammonia isn't typical, the presence of ammonium ions in solution can lead to the formation of ammonia in a slightly acidic medium due to the equilibrium with its conjugate acid and base:

NH4+(aq) + H2O(l) <=> H3O+(aq) + NH3(aq).

When it comes to bases, they do indeed react with ammonium salts like ammonium sulfate, because bases can accept protons from the ammonium ion, releasing ammonia:

Base + NH4+ (aq) → BaseH+ (aq) + NH3 (g).

As for Statement 2, it is false since acids turn blue litmus paper red, not blue. It is bases that turn red litmus paper blue, and this is one of their characteristic properties, like turning phenolphthalein pink and feeling soapy to the touch.

User Martin Zugnoni
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