Rates of Reaction

How does a catalyst work in speeding up a reaction?

• by lowering the activation energy (minimum energy needed for the reaction to take place)

• by giving the reactants more energy

• by increasing the number of reactant particles

• by increasing the temperature

Tags

NGSS.HS-PS1-4

Why does a higher concentration increase the rate of reaction?

• it increases the amount of reactants

• it lowers the activation energy

• it increases the energy of particle collisions

• it increases the frequency of particle collisions

Tags

NGSS.HS-PS1-5

Which of the following increases the reaction rate?

• less surface area

• lower temperature

• more particle size

• increased concentration

Tags

NGSS.HS-PS1-5

NGSS.HS-PS1-6

What makes an effective collision?

• When molecules collide.

• When molecules collide with the proper orientation.

• When molecules collide with proper orientation and enough kinetic energy.

• High Temperature.

________ the concentration ______ the reaction rate.

• increasing; decreases

• increasing; increases

• decreasing; increases

• decreasing; does not effect

Tags

NGSS.HS-PS1-5

Enzymes in your body act as catalysts. Thus, the role of enzymes is to___________.

• inhibit chemical reactions.

• increase the rate of chemical reactions.

• decrease the rate of chemical reactions.

A substance that slows down or stops a chemical reaction is called a(n)______________.

• concentrate

• catalyst

• inhibitor

• product

Which of the following would react fastest in sweet tea?

• a sugar cube

• a sugar cube cut in half

• a sugar cube cut in fourths

• a sugar cube crushed into powder

The minimum amount of energy needed for substances to react is called__________.

• Activation Energy

• Catalyst Energy

• Endothermic Energy

• Exothermic Energy

Tags

NGSS.HS-PS1-4

Why does a higher temperature increase the rate of a reaction?

• it increases both the frequency and energy of particle collisions

• it only increases the frequency of particle collisions

• it only increases the energy of particle collisions

• it reduces the activation energy of the reaction

Tags

NGSS.HS-PS1-5