Energy transfer in Chemical Reaction

What is a chemical reaction?

A process where chemicals come together to form new substances.

In a chemical reaction, what are the starting chemicals called?

Reactants.

In a chemical reaction, what is the resulting substance called?

Product.

What does the collision theory state regarding chemical reactions?

For a chemical reaction to occur, the particles in reactants must collide with each other.

What is the rate of reaction?

A measure of how fast a chemical reaction occurs.

Name three factors that influence the rate of a chemical reaction.

Temperature, surface area of reactants, and concentration of reactants.

How does increasing temperature affect the rate of reaction?

Heat gives particles more energy, causing them to move faster and collide more frequently, resulting in a faster reaction.

How does increasing the concentration of reactants affect the rate of reaction?

It increases the number of particles present, which leads to more collisions and a faster reaction rate.

What is surface area in the context of chemical reactions?

A measure of how much of a substance is exposed for collisions to occur.

How does increasing surface area affect the rate of reaction?

It provides more area for collisions to occur, which increases the rate of reaction.

What is a catalyst?

A substance that speeds up the rate of a chemical reaction.

What chemical is used to speed up the production of oxygen from hydrogen peroxide?

Manganese dioxide.

What is the word equation for the production of oxygen using hydrogen peroxide?

Hydrogen Peroxide + Manganese dioxide -> Water + Oxygen.

How can you test for the presence of oxygen gas?

Oxygen will relight a glowing splint.

What two types of substances react to produce carbon dioxide?

An acid and a carbonate.

What is the word equation for the reaction between hydrochloric acid and calcium carbonate?

Hydrochloric acid + Calcium Carbonate -> Calcium Chloride + Water + Carbon Dioxide.

How can you test for the presence of carbon dioxide gas?

It will extinguish a lit splint.

What is an exothermic reaction?

A reaction that releases heat, causing the temperature of the surroundings to increase.

What is an endothermic reaction?

A reaction that absorbs heat, causing the temperature of the surroundings to decrease.

What are energy profile diagrams used for?

To show energy transfers during chemical reactions.

What is activation energy?

The minimum amount of energy required to start a chemical reaction.

What is a simple mnemonic to remember exothermic vs endothermic reactions?

Exothermic means heat exits; Endothermic means heat enters.

What is the primary tip for answering multiple-choice exam questions on chemical reactions?

Use the process of elimination by starting with the options you are sure of.