chemical equilibrium

At elevated temperatures ammonium carbonate, NH₂COONH₄, is in equilibrium with NH₃ and CO₂ according to the equation;

NH₂COONH₄(s) ↔ 2 NH₃(g) + CO₂(g)

What is the equilibrium expression for this reaction?

• K = 2 [NH₃][CO₂]

  [NH₂COONH₄]

• K = [NH₃]²[CO₂]

  [NH₂COONH₄]

• K = 2 [NH₃][CO₂]

• K = [NH₃]²[CO₂]

Tags

NGSS.HS-PS1-6

What is the equilibrium-constant expression for 
CO₂(g) + H₂(g) ↔ CO(g) + H₂O(l)

• K_c= [CO][H₂O] / [CO₂][H₂]  
• K_c= [CO₂][H₂] / [CO]
• K_c= [CO₂][H₂] / [CO][H₂O]
• K_c= [CO] / [CO₂][H₂]  

Tags

NGSS.HS-PS1-6

For the following reaction: H₂(g) + Cl₂ (g) ↔ 2HCl(g), calculate the concentration of HCl when K_eq= 2.3x10^-5, [H₂]= 0.0056mol, [Cl₂]= 0.0048mol.

• 6.2 x 10^-10 M

• 2.5 x 10^-5 M

• 1.1 M

• 1.2 M

Tags

NGSS.HS-PS1-6

NGSS.HS-PS1-7

What are the two factors to look for when determining if the reaction is at equilibrium?

• Forward reaction rate is faster than the reverse and concentrations are equal
• Forward and reverse reaction rates are equal and concentration is constant
• Forward and revers reaction rates are equal and concentration is equal
• Forward reaction rate is faster than the reverse and concentration is equal

Tags

NGSS.HS-PS1-5

NGSS.HS-PS1-6

At what time the reaction reached equilibrium?

• t₁
• t₂
• t₃
• t₄

Tags

NGSS.HS-PS1-6

Which of the following is the condition needed to establish the equilibrium?

• Constant Temperature

• Products and reactants should be in constant dynamic motion

• All reactants and products should be in closed system

• All of the above

Tags

NGSS.HS-PS1-6

What are [A] and [B]?

• concentration of reactants
• concentration of products
• energy of reactants
• energy of products

Tags

NGSS.HS-PS1-5

NGSS.HS-PS1-6

What is the value for Kc if [CO] = 0.025, [H₂] = 0.013 and [CH₃OH] = 0.0028 for the following reaction?

CH₃OH(g) ⇌ CO(g) + 2 H₂(g)

• 0.12

• 9.1 × 10^-7

• 6.6 × 10²

• 1.5 × 10^-3

• 8.6

Tags

NGSS.HS-PS1-6

What is the correct formula for the equilibrium constant

• $K\ =\ \frac{\text{Products}}{\text{Reactants}}$

• $K\ =\ \frac{\text{Reactants}}{\text{Products}}$

What is a characteristic of a system in equilibrium except ?

• Occurs only in closed system

• Concentration of product and reactant not change

• Concentration of product appearing per unit time

• Rate of forward reaction equals the rate of reverse reaction

Tags

NGSS.HS-PS1-6