Chemical Equilibrium & Kinetics

Chemical equilibrium is defined as the state in which the concentrations of reactants and products remain constant over time. Which of the following best describes this state?

• The forward and reverse reactions occur at different rates.

• The forward and reverse reactions occur at the same rate.

• The concentrations of reactants are higher than products.

• The concentrations of products are higher than reactants.

Tags

NGSS.HS-PS1-6

Which theory explains the conditions under which chemical reactions occur?

• Collision theory

• Quantum theory

• Relativity theory

• String theory

Tags

NGSS.HS-PS1-5

Define concentration in terms of chemical reactions.

• The amount of a substance in a given volume.

• The speed at which a chemical reaction occurs.

• The energy required to start a chemical reaction.

• The temperature at which a reaction takes place.

Tags

NGSS.HS-PS1-5

What is meant by reaction rate in chemical kinetics?

• The speed at which reactants are converted into products.

• The amount of energy required to start a reaction.

• The equilibrium constant of a reaction.

• The temperature at which a reaction occurs.

Tags

NGSS.HS-PS1-5

A catalyst is:

• a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.

• a substance that decreases the rate of a chemical reaction and is consumed in the process.

• a reactant that is completely used up in a chemical reaction.

• a product formed in a chemical reaction.

Tags

NGSS.HS-PS1-5

What is surface area in the context of chemical reactions?

• The total area of the surface of a three-dimensional object.

• The measure of how much exposed area a solid object has.

• The amount of space occupied by a substance.

• The rate at which a chemical reaction occurs.

Kinetic energy is the energy possessed by an object due to its:

• Position

• Motion

• Temperature

• Shape

Tags

NGSS.HS-PS2-3

NGSS.HS-PS3-2

An endothermic reaction is a chemical reaction that:

• Releases heat to the surroundings

• Absorbs heat from the surroundings

• Does not involve any heat exchange

• Produces light as a byproduct

Tags

NGSS.HS-PS1-4

Define exothermic reaction.

• a chemical reaction that releases energy to its surroundings.

• a chemical reaction that absorbs energy from its surroundings.

• a chemical reaction that does not involve energy change.

• a chemical reaction that only occurs at high temperatures.

Tags

NGSS.HS-PS1-4

What is pressure?

• the amount of force exerted per unit area of a surface.

• the speed at which an object moves.

• the volume of a liquid in a container.

• the temperature of a substance.