Chemical Elements and the Periodic Table: Properties and Structure

Metals and Non-Metals

Since antiquity, items such as gold, silver, etc. have been discovered over time. Up to now, more than 100 have been identified. A first classification of items, focusing on appearance and physical properties, allows for 2 groups: metals and non-metals.

Metals and Non-Metals

To distinguish one from the other, we will name characteristics that make them different:

Metallic Elements

  • Have a characteristic brightness.
  • Are opaque and good conductors of heat and electricity.
  • Are usually
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Thermodynamics Problems and Solutions: Ideal Gas Law

Ideal Gas Law and Thermodynamics Problems

Problem 1

An ideal gas occupies a volume of 100 cm3 at 20°C and a pressure of 100 Pa. Determine the number of moles of gas in the vessel.

1 Pa * 1 m3 = 1 Joule

PV = nRT

100 Pa * 10 * 10-7m3 = n

8.31 * 293

n = 4.11 * 10-6

Problem 2

Calculate the volume occupied by one mole of gas under normal conditions.

PV = nRT

1 atm * V = 1 mol * 0.082 * 273

V = 22.4 L

Problem 3

Helium is introduced into a mobile container. The initial pressure, volume, and temperature of the gas are

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Acid-Base Titration and Salt Hydrolysis in Chemistry

Acid-Base Titration

In both industrial processes and in the laboratory, it is very common to determine the amount of acid or base in a sample. Titration, specifically acid-base titration, is a method of chemical analysis used to determine the unknown concentration of an acidic or basic solution. This is achieved by using a standard solution, which is a basic or acidic solution of known concentration.

The experimental procedure involves placing a known volume of the solution to be analyzed in a conical

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Chemical Properties and Reactions: Elements, Compounds, and Laws

Periodic Properties of Elements

Atomic Radius

The atomic radius is the distance from the center of the nucleus to the area corresponding to the outermost level. Over a period, the radius decreases from left to right.

Ionization Energy

Ionization energy is the energy required to form an ion (cation); the energy that must be delivered to an isolated atom to remove an electron. The ionization increases from left to right, and in a group, it decreases from top to bottom.

Electronegativity

Electronegativity

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Chemical Bonding: Types, Properties, and Structures

Unit 2: Chemical Bonding

Ionic Bond – Lattice Energy

Formula

Where K is Coulomb’s constant, Z represents the charges of the ions, e is the absolute value of the electron charge, N is Avogadro’s number, d is the internuclear distance, m is the Madelung constant, and ε is the Born exponent.

Born-Haber Cycle and Lattice Energy

The Born-Haber cycle is a thermodynamic cycle that analyzes all the processes involved in the formation of one mole of an ionic compound from its constituent elements in their most stable

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Understanding Matter and Energy: Properties, Laws, and Atomic Structure

**Physical Property**

All properties of matter are subject to the scientific method: observation, hypothesis formulation, experimentation, communication of results, and extraction of conclusions.

**Physics**

Studies the changes in materials in which the substances are not transformed into other new substances.

**Chemistry**

Studies the transformations that substances can experience: structure, composition, and properties.

**Absolute Error**

The difference in absolute value between the approximate value

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