Question

The equilibrium-constant of the reaction NO2(g)+NO3(g)⇌N2O5(g) is K=2.1×10−20. What can be said about this reaction? a. At equilibrium the concentration of products and reactants is about the same. b. At equilibrium the concentration of products is much greater than the concentration of reactants. c. At equilibrium the concentration of reactants is much greater than that of products. d. There are no reactants left over once the reaction reaches equilibrium.

Answer 1

`\boxed{\text{c. The concentration of reactants is much greater than that of products.}}`

Step-by-step explanation:

NO₂ + NO₃ ⇌ N₂O₅; K = 2.1 × 10⁻²⁰

We often write K as

`K = \frac{[\text{Products}]}{[\text{Reactants}]}`

If K is large, more of the molecules exist as products.

If K is small, more of the molecules exist as reactants.

`\text{Since K is small, }\\\boxed{\textbf{the concentration of reactants is much greater than that of products.}}`

a. b., and d. are wrong. The concentration of reactants is greater.