ch 10: Reaction Rates in Equilibrium

What is an exothermic reaction?

A reaction where heat is a product, leaving the reaction and it feels warm.

What does an endothermic reaction do?

It absorbs heat as a reactant, causing the reaction to feel cold.

Define reaction rate.

The speed at which a chemical reaction occurs.

List one way to measure reaction rates.

Changes in concentration.

What is collision theory?

A theory that states collisions are key for reactions, requiring molecules to be in close contact, collide, have sufficient energy, and correct orientation.

How does surface area affect reaction rates?

Greater surface area allows for more collisions, leading to faster reactions.

What happens to reaction rates with increased temperature?

Higher temperatures increase molecular speed, resulting in more collisions and faster reactions.

What is the effect of adding a reactant according to Le Chatelier's Principle?

It causes a shift towards the product to produce more of it.

What is Le Chatelier’s Principle?

A principle that states stressing a reversible reaction causes a change in the reaction rate and equilibrium position.

What occurs when pressure is increased in a reaction involving gases?

The reaction shifts towards the side with fewer moles of gas.

How do catalysts affect chemical reactions?

They speed up the reaction without being consumed, shifting it towards the product.

Describe the effect of increasing temperature on an exothermic reaction.

It causes a shift away from heat (to the right) in the reaction.

What happens when a product is added in a reversible reaction?

It causes a shift towards the reactant to utilize the added product.

How does removing a reactant affect a reaction?

It causes a shift towards the reactant to replace what was removed.

What is the effect of temperature decrease on an exothermic reaction?

It causes a shift towards heat (to the left) in the reaction.

Define a catalyst in the context of chemical reactions.

A substance that speeds up the forward reaction and shifts the equilibrium to the right towards the product.