The equilibrium constant, K

Answer Key - Grade 10 Science Worksheet

Circle the best answer, or write your answer on the line.

1. 1.

   At equilibrium for N₂O₄ ⇌ 2 NO₂, [N₂O₄] = 0.04 mol/L and [NO₂] = 0.1 mol/L. What is K, Ari?

   0.25
2. 2.

   At equilibrium for N₂O₄ ⇌ 2 NO₂, [N₂O₄] = 0.3 mol/L and [NO₂] = 0.06 mol/L. What is K, Bo?

   0.012
3. 3.

   At equilibrium for N₂O₄ ⇌ 2 NO₂, [N₂O₄] = 0.1 mol/L and [NO₂] = 0.05 mol/L. What is K, Esme?

   0.025
4. 4.

   Which is K for H₂ + I₂ ⇌ 2 HI, Kira?

   • ([H₂][I₂]) ÷ [HI]²
   • 2[HI] ÷ ([H₂][I₂])
   • [HI]² ÷ ([H₂][I₂])
5. 5.

   Which is K for CaCO₃(s) ⇌ CaO(s) + CO₂(g), Luz?

   • [CaCO₃] ÷ [CaO]
   • [CaO][CO₂] ÷ [CaCO₃]
   • [CO₂]
6. 6.

   For a mixture, Q is smaller than K. Which way does the reaction go, Milo?

   • Neither way
   • Backward, toward reactants
   • Forward, toward products
7. 7.

   For a mixture, Q is larger than K. Which way does the reaction go, Noah?

   • Backward, toward reactants
   • Neither way
   • Forward, toward products
8. 8.

   For a mixture, Q equals K. What happens, Pia?

   • No net change: it's at equilibrium
   • It speeds up in the forward direction
   • It runs backward fast
9. 9.

   Extra reactant is added to a mixture at equilibrium. What happens, Ren?

   • K rises to match Q
   • Q drops below K; it shifts forward
   • Q rises above K; it shifts back
10. 10.

    Does adding reactant change the value of K, Zee?

    • Yes: K falls with more reactant
    • No: K stays at the same temperature
    • Yes: K rises whenever reactant is added