what happens when h3po4 is heated with zinc and hcl?

When H3PO4 (phosphoric acid) is heated with zinc (Zn) and HCl (hydrochloric acid), a chemical reaction called a displacement reaction or a redox reaction occurs. The reaction can be represented by the following balanced equation:

2 H3PO4 + 3 Zn + 6 HCl → 3 ZnCl2 + 2 H2O + H3PO4

Now, let's break down the reaction and explain what happens step by step:

1. Dissociation of H3PO4: Phosphoric acid (H3PO4) dissociates in water to produce H⁺ (hydrogen ions) and H2PO4⁻ (dihydrogen phosphate ions).

H3PO4(aq) → H⁺(aq) + H2PO4⁻(aq)

2. Reaction between Zn and HCl: Zinc (Zn) reacts with hydrochloric acid (HCl) to produce hydrogen gas (H2) and zinc chloride (ZnCl2).

Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g)

3. Reduction of Phosphoric Acid: The hydrogen gas (H2) produced in the previous step now reacts with the phosphoric acid (H3PO4) to reduce it.

2 H⁺(aq) + H2(g) → 2 H2O(l)

4. Overall Reaction: Combining all the reactions, we get the overall balanced equation:

2 H3PO4(aq) + 3 Zn(s) + 6 HCl(aq) → 3 ZnCl2(aq) + 2 H2O(l) + H3PO4(aq)

In simple terms, when H3PO4 is heated with zinc and hydrochloric acid, it produces zinc chloride, water, and some leftover phosphoric acid.

Remember, it's always important to handle chemicals safely and perform such experiments under proper laboratory conditions.