Chemical Reactions and Equations Lecture Notes

Vocabulary flashcards covering the fundamental concepts of chemical reactions, equations, reaction types, and oxidation effects as described in the Chapter 1 transcript.

Chemical Reaction

A process that occurs whenever a chemical change takes place, where the nature and identity of the initial substance have changed.

Magnesium Oxide

A white powder formed by the reaction between magnesium and oxygen present in the air when a magnesium ribbon burns with a dazzling white flame.

Reactants

The substances that undergo chemical change in a reaction, written on the left-hand side (LHS) of a chemical equation.

Product

The new substance formed during a chemical reaction, written on the right-hand side (RHS) of a chemical equation.

Skeletal Chemical Equation

A chemical equation where the number of atoms of each element is not the same on both sides, meaning the mass is not balanced.

Law of Conservation of Mass

A principle stating that mass can neither be created nor destroyed in a chemical reaction; the total mass of elements in the products must equal the total mass of elements in the reactants.

Balanced Chemical Equation

An equation where the number of atoms of each element remains the same before and after a chemical reaction.

Hit-and-trial method

A method of balancing chemical equations by making trials to balance the equation using the smallest whole number coefficient.

Aqueous (aq)

A notation used in chemical equations to indicate that a reactant or product is present as a solution in water.

$$340\,atm$$

The specific pressure condition indicated above the arrow for the reaction between $CO(g)$ and $2H_2(g)$ to form $CH_3OH(l)$.

Combination Reaction

A reaction in which a single product is formed from two or more reactants.

Quick Lime

Common name for Calcium oxide ($CaO(s)$) which reacts vigorously with water to produce slaked lime.

Slaked Lime

Common name for Calcium hydroxide ($Ca(OH)_2(aq)$) produced by the reaction of calcium oxide and water; used for whitewashing walls.

Exothermic Chemical Reactions

Reactions in which heat is released along with the formation of products, such as the burning of natural gas or respiration.

Respiration

An exothermic process where glucose ($C_6H_{12}O_6(aq)$) combines with oxygen in the cells of the body to provide energy.

Decomposition Reaction

A reaction where a single reactant breaks down to give simpler products.

Thermal Decomposition

A decomposition reaction that is carried out specifically by heating the reactant.

Endothermic Reactions

Reactions in which energy is absorbed from the surroundings, usually in the form of heat, light, or electricity.

Displacement Reaction

A reaction where a more reactive element, such as Zinc or Lead, displaces or removes another element like Copper from its compound.

Precipitate

An insoluble substance formed during a chemical reaction that produces a solid within a liquid solution.

Double Displacement Reaction

A reaction in which there is an exchange of ions between the reactants to form new compounds.

Oxidation

The gain of oxygen or the loss of hydrogen by a substance during a chemical reaction.

Reduction

The loss of oxygen or the gain of hydrogen by a substance during a chemical reaction.

Redox Reactions

Reactions where one reactant gets oxidised while the other gets reduced simultaneously; also known as oxidation-reduction reactions.

Corrosion

The process where a metal is attacked by substances around it such as moisture or acids; examples include the rusting of iron or green coating on copper.

Rancidity

A condition occurring when fats and oils are oxidised, leading to a change in their smell and taste.

Antioxidants

Substances added to foods containing fats and oils to prevent oxidation and slow down the process of rancidity.