Early Equilibrium quiz,

What is equilibrium as it applies to chemical changes?

Answer: the study of ...

• how fast a chemical change takes place

• how high the activation energy (Ea) is for a chemical change

• how forward a chemical reaction goes forward

• how often particles collide and interact per second

Tags

NGSS.HS-PS1-6

What is equal during chemical equilibrium?

• the forward & reverse rates of reaction in a closed system

• the concentration or pressure of reactants & products

• the amount of activation energy (Ea) in both directions of the chemical change

• the forward & reverse rates of reaction in an open system

Tags

NGSS.HS-PS1-5

What is constant at chemical equilibrium?

• The temperature of the system.

• The amount of reactant.

• The amount of product.

• All of the other answers are correct.

Tags

NGSS.HS-PS1-6

Which is/are false about an equilibrium constant?

• it is a constant relating amount of product to reactants

• it is a constant relating speed of reaction to concentrations of reactants to their reaction order exponent

• it is a constant that has units

• it is a constant that is temperature specific

• it is a constant that includes concentration or pressure, as well as stoichiometric coefficients

What is favored when your Keq equilibrium  constant is significantly above 1 in its value.

• reactants

• products

• amount of catalyst

• reactants & products are equally favored

Tags

NGSS.HS-PS1-6

What is favored when your Keq equilibrium  constant is significantly less than 1 in its value.

• reactants

• products

• amount of catalyst

• reactants & products are equally favored

For a chemical change that usually favors the reactants, what is favored at equilibrium when your chemical reaction is accelerated by adding a catalyst.

• reactants

• products

• neither

• both

Tags

NGSS.HS-PS1-6

What states or phases are  not included in the calculation of the equilbrium constant Keq?

• pure solids

• pure liquids

• gases

• aqueous ions

• pure solids & liquids

The concentration or pressure of reactants is equal to the concentration or pressure of products when the chemical change is at equilibrium.

• true

• false

Tags

NGSS.HS-PS1-6

If in the chemical change: A(aq) + B(aq) -> C (aq) ,

and more A is added, then what happens?

• The Kc or Keq for this aqueous reaction stays the same.

• The Kc or Keq for this aqueous reaction changes.

• This aqueous reaction shifts "to the right" toward products.

• This aqueous reaction shifts "to the left" toward reactants.

Tags

NGSS.HS-PS1-5