Question

Which formula equation shows a reversible reaction? a. 2Na+F2–> 2NaF b. CaCO3–> CaO+CO2 c. NH4CI(s)—–NH3(g.+HCI(g. 2H2O2(aq)–pt—> 2H2O(I)+O2(g.?

Answer 1

Answer:

just did edge test, got 100%:

C. NH4Cl(s)<-->NH3(g) + HCl(g)

Answer 2

Answer:

• The choice c. NH₄CI(s) ⇄ NH₃(g) + HCI(g) is the reversible reaction.

Explanation:

The formula equations given are:

• a. 2Na + F₂ → 2NaF

• b. CaCO₃ → CaO + CO₂

• c. NH₄CI(s) ⇄ NH₃(g) + HCI(g)

                             

• d. 2H₂O₂(aq)  →  2H₂O(I)+O₂(g)

        [there is also a Pt symbol over the arrow, which means that Pt

          is a catalyst]

Reversible reactions are reactions that may happen in both directions, i.e. there is a direct or forward reaction and a reverse reaction.

The symbol used to show a reversible reaction is the double arrow (⇄).

The double arrow shows tha both left side substances and right side substances are reactants and products.

In the reaction NH₄CI(s) ⇄ NH₃(g) + HCI(g) you have:

• NH₄CI(s) → NH₃(g) + HCI(g) is the direct reaction. In this, NH₄CI(s) is the reactant and NH₃(g) + HCI(g) are the products.

• NH₄CI(s) ← NH₃(g) + HCI(g) (notice the arrow goes from right to left)  is the reverse reaction. In this, NH₄CI(s) is the product and both NH₃(g) and HCI(g) are the reactants.

All the other equations are written with a single arrow, so they are not reversible reactions.