Understanding Acids and Bases: Theories, Strength, and Dissociation
Arrhenius Theory of Acids and Bases
An electrolyte is a substance that, in aqueous solution, conducts electricity. Svante Arrhenius established that when an electrolyte dissolves in water, it dissociates into two electrically charged ions with opposite charges (positive: cation, negative: anion). This theory is valid for any substance that conducts electricity in aqueous solution. Since acids and bases conduct electricity, these ideas were applied to them. An acid is any substance that dissociates
Read MoreUnderstanding Matter: Properties, Scientific Method, and Gas Laws
Properties of Matter
General Properties
These are values that serve to identify a substance, such as temperature, mass, and volume.
Characteristic Properties
These are unique and specific values for each substance, including density, melting point, boiling point, hardness, water solubility, and electrical conductivity.
Density
The amount of mass per unit volume (e.g., lead is dense, cork is less dense).
Hardness
The resistance a substance has to scratching or abrasion (e.g., diamond is very hard, talc is
Chemical Titration Methods: Complexometric & Precipitation Analysis
Complexometric Titrations
Complexometric titrations are a type of volumetric analysis involving titrants that form a soluble complex with the analyte (the substance being valued). In any complex, two main parts are distinguished: the central atom (usually a metal atom or ion) and the ligand.
Types of Ligands in Complexometric Titrations
Atomic or Molecular Ligands
When the ligand is an atom or molecule, the resulting complex is often referred to as a coordination compound. For neutral ligands, the overall
Chemistry Fundamentals: Substances, Mixtures, and Properties
What is a Mixture?
It is the union of two or more substances in different proportions.
What is a Pure Substance?
These are formed by identical particles, such as water, alcohol, and oxygen.
Types of Mixtures
Homogeneous Mixtures
They are those whose components are indistinguishable to the naked eye and look the same throughout the mixture.
Heterogeneous Mixtures
These are mixtures whose components are distinguishable to the naked eye.
Differences of Colloid Solutions
A colloid solution is observed using an
Read MoreUnderstanding Chemical Systems and Their Phases
System is the set of chemicals selected for study in isolation from the outside environment. It is a mixture of simple and composite bodies in varying proportions, among which can produce physical, chemical, or physical-chemical phases. Any part of a system that has properties physically distinguishable from other single components or composite bodies that make up the system initially can be distinguished in the system in equilibrium. Solid solutions: their classes. Plot your cooling solid solution
Read MoreAtomic Structure, Electron Configuration, and Chemical Properties
Bohr’s Atomic Model
Bohr’s model for the hydrogen atom aimed to explain its electronic structure and justify its atomic spectrum. It was based on three main postulates:
- The electron revolves around the nucleus in specific circular orbits of fixed energy.
- Only orbits where electrons possess specific, quantized energy values are allowed. These orbits are called energy levels.
- When an electron transitions from a higher energy level to a lower one, the energy difference is emitted as light (a photon).