Chemistry Catalysts Flashcards

Questions and Answers

Photosynthesis is an example of?

An endothermic reaction (correct)

A catalytic reaction

An exothermic reaction

A thermochemical reaction

What must happen before a chemical reaction can begin?

The activation energy must be reached.

Which term describes an enzyme?

Catalyst

Which is the best definition of activation energy?

The energy required to form or break the bonds of reactant molecules. Signup and view all the answers

How does a catalyst speed up a chemical reaction?

The catalyst makes lower energy pathways available. Signup and view all the answers

What describes a chemical reaction?

Bonds between atoms break and new bonds form. Signup and view all the answers

What should a researcher measure to determine if substance A affects the reaction rate?

First, he should measure how long it takes for the liquid to become clear if X and Y are mixed together. Then, he should measure how long it takes if he also adds substance A to X and Y. Signup and view all the answers

The lock-and-key mechanism refers to?

The complementary shapes of an enzyme and a substrate. Signup and view all the answers

What happens to the amount of catalyst at the end of a reaction?

The amount of catalyst remains the same at the end as at the beginning of the reaction. Signup and view all the answers

Study Notes

Photosynthesis and Endothermic Reactions

Photosynthesis is classified as an endothermic reaction, meaning it absorbs energy from the surroundings.

Initiation of Chemical Reactions

Activation energy must be reached for a chemical reaction to commence; it is the minimum energy threshold required.

Enzymes as Catalysts

Enzymes function as catalysts, substances that accelerate chemical reactions without being consumed in the process.

Understanding Activation Energy

Activation energy is defined as the energy necessary to either form or break the bonds between reactant molecules.

Role of Catalysts

Catalysts enhance the speed of chemical reactions by providing lower energy pathways, making reactions occur more efficiently.

Nature of Chemical Reactions

A chemical reaction involves breaking existing bonds between atoms and forming new bonds, leading to the transformation of reactants into products.

Experimental Design in Reaction Rate Analysis

To investigate if an inorganic substance (A) affects the reaction rate between two colored liquids (X and Y), one should first time the clarity of the mixture of X and Y, then repeat the timing with the addition of substance A. This experiment will reveal if A serves as a catalyst.

Lock-and-Key Mechanism

The lock-and-key mechanism describes the specific complementary shapes of an enzyme and its substrate, enabling precise biochemical interactions.

Catalyst Conservation in Reactions

At the conclusion of a chemical reaction, the amount of catalyst present remains unchanged compared to its initial quantity, highlighting its role in facilitating but not altering the overall reaction mass.

Description

Explore essential concepts related to catalysts and chemical reactions with these flashcards. Key terms such as photosynthesis, activation energy, and enzymes are defined for better understanding. Enhance your chemistry knowledge with this focused study tool.