Equilibria

Question 1

What is Le Chatiliers principle?

Answer 1

When a system in dynamic equilibrium is subjected to change the position of the equilibrium will shift to oppose the change

Question 2

What are the conditions of dynamic equilibrium?

Answer 2

• constant concentration of reactants and products
• rate of forwards reaction same as backwards reaction
• reaction in a closed system

Question 3

What type of reaction is it if delta H is positive?

Answer 3

endothermic

Question 4

What type of reaction is it if delta H is negative?

Answer 4

exothermic

Question 5

What is the effect of adding a catalyst on equilibrium position?

Answer 5

Adding a catalyst does not change the equilibrium position but increases rate at which equilibrium is established

Question 6

What is the effect of temperature on equilibrium position?

Answer 6

forwards reaction: exo, backwards reaction: endo

increasing temperature causes position of equilibrium to shift to the left (endothermic direction)

decreasing temperature causes position of equilibrium to shift to the right (exothermic direction)

Question 7

What is the effect of concentration on equilibrium position?

Answer 7

increasing concentration of reactants will cause position of equilibrium to shift to make more product

increasing concentration of products will cause position of equilibrium to shift to make more of reactants

Question 8

What is the effect of pressure on equilibrium position?

Answer 8

Increasing pressure will cause position of equilibrium to shift to side with fewest moles of gas

Decreasing pressure will cause position of equilibrium to shift to side with more moles of gas

Question 9

What does it mean if Kc is greater than 1?

Answer 9

concentration of products greater than concentration of reactants

Question 10

What does it mean if Kc is less than 1?

Answer 10

concentration of reactants greater than concentration of products