Chemical Reactions and Energy Review

Flashcards covering chemical nomenclature, balancing reactions, collision theory, and thermodynamics based on the lecture transcript.

Sodium chloride

$$NaCl$$

Magnesium fluoride

$$MgF_2$$

Trisilicon dioxide

$$Si_3O_2$$

Copper(II) oxide

$$CuO$$

Sulfurous acid

$$H_2SO_3$$

Hydrosulfuric acid

$$H_2S$$

Phosphorous tribromide

$$PBr_3$$

Acetic acid

$$CH_3COOH$$

Nitrous acid

$$HNO_2$$

Trinitrogen tetroxide

$$N_3O_4$$

Exothermic Reaction

A reaction that releases energy to the surroundings, characterized by a positive $\Delta T$ (temperature increase) and a negative $\Delta H$.

Endothermic Reaction

A reaction that absorbs energy from the surroundings, characterized by a negative $\Delta T$ (temperature decrease) and a positive $\Delta H$, where the products have more potential energy than the reactants.

Activation Energy ($E_a$)

The minimum amount of energy required to initiate a chemical reaction, representing the energy gap between the reactants and the activated complex.

Activated Complex

A temporary transition state at the highest energy point of a reaction (the top of the energy hill) where reactants are converting into products.

Enthalpy Change ($\Delta H$)

The difference between the potential energy of the products and the potential energy of the reactants ($\text{PE}_{\text{products}} - \text{PE}_{\text{reactants}}$). For exothermic reactions, this value is negative.

Collision Theory

States that for a reaction to occurs, particles must collide with sufficient kinetic energy and the correct geometric orientation.

Reaction Rate Factors

Increasing temperature, increasing concentration, or adding a catalyst are three ways to speed up the rate of a chemical reaction.

Catalyst

A substance that speeds up a reaction by lowering the activation energy ($E_a$) without changing the $\Delta H$ or being consumed by the reaction.

Combustion of Heptane

The reaction of $C_7H_{16}$ with oxygen ($O_2$) to produce carbon dioxide ($CO_2$) and water ($H_2O$).

Neutralization Reaction

A specific type of double replacement reaction where an acid (like nitric acid) and a base (like iron(III) hydroxide) react to produce a salt and water.

Kinetic Energy in Heating

As a substance heats up, the molecules speed up and their kinetic energy increases, often leading to increased space between molecules.

Chemical Potential Energy

Energy stored within the chemical bonds of reactants or products, represented as potential energy (PE) in energy diagrams.