Chemical Equilibrium-BSEK-Class 10

This symbol indicates that a reaction is ____________

• reversible

• irreversible

When the rate of the forward reaction is equal to the rate of backward reaction, the system is said to be in

• Chemical Equilibrium

• Chemical Balance

• Stoichiometry

• Chemical Reaction

Forward reaction is

• Reactants to products (left to right)

• Products to reactants (right to left)

• Always reversible

• Always endothermic

Who was the scientist who discussed changes in equilibrium?

• Newton

• Bob

• Goldberg

• Le Chatelier

What is the unit when measuring concentration?

• moles

• M

• molecules

• avogadros number

How do you measure Molarity?

• moles/Liters

• moles/grams

• grams/Liter

• liter/moles

2A + 3B  <---->  2AB
The forward reaction points towards the __________.

• left

• right

• up

• down

Which is the correct equilibrium constant expression for the following reaction?

Fe₂O_3(s) + H_2(g) —> Fe_(s) + H₂O_(g)

• K = [H₂O]3 / [H₂]³

• K = [Fe₂O₃] [H₂]³ / [Fe]²[H₂O]³

• K = [Fe]²[H₂O]³ / [Fe_2O₃] [H₂]³

• K= [Fe] [H₂O] / [Fe₂O₃] [H₂]

• K = [H₂] / [H₂O]

The equilibrium between carbon dioxide gas and carbonic acid is very important in biology and environmental science. CO_2(g) + H₂O_(l) —> H₂CO3(aq)

Which one of the following is the correct equilibrium constant expression (Kc) for this reaction?

• Kc= 1/ [H₂CO₃]

• Kc= [CO₂]/ [H₂CO₃]

• Kc= [H₂CO₃] / [CO₂]

• Kc= [CO₂] [H₂O] / [H₂CO₃]

• Kc= [H₂CO₃] / [CO₂] [H₂O]

Calculate Kc for the reaction HI_(g) —> H_2(g) + I_2(g) given that the concentrations of each species at equilibrium are as follows: [HI] = 0.85 mol/L, [I₂] = 0.60 mol/L, [H₂] = 0.27mol/L.

• 0.19

• 0.22

• 4.5

• 5.25

• 160