Domingo, Jhon Lyod C.

BSC-2 DELTA

General Chemistry

1. Define the

Following:

a. Chemistry

-Chemistry is the scientific study of matter, its properties, composition, structure,

and the changes it undergoes during chemical reactions. It explores the
interactions between atoms, molecules, and ions to understand the principles
governing the behavior of substances. Chemistry plays a crucial role in various
scientific disciplines, industries, and everyday life, influencing fields such as
medicine, materials science, environmental science, and agriculture.

b. Inorganic Chemistry

-Inorganic chemistry is a branch of chemistry that focuses on the study of

inorganic compounds, which are compounds that do not contain carbon-hydrogen
(C-H) bonds. Instead, inorganic chemistry deals with the properties, behavior, and
synthesis of elements and inorganic compounds, including metals, minerals, salts,
coordination compounds, and organometallic compounds. Inorganic chemistry
plays a vital role in various fields such as materials science, catalysis,
environmental science, and bioinorganic chemistry.

c. Organic Chemistry

-Organic chemistry is a branch of chemistry that deals with the study of carbon-
containing compounds and their properties, structure, synthesis, reactions, and
applications. Carbon forms the backbone of organic molecules, often bonded with
hydrogen, oxygen, nitrogen, and other elements. Organic chemistry encompasses
a wide range of topics, including hydrocarbons (such as alkanes, alkenes, and
alkynes), functional groups (such as alcohols, ethers, aldehydes, ketones,
carboxylic acids, and esters), stereochemistry, reaction mechanisms, and organic
 synthesis. It is crucial to many scientific disciplines, including biochemistry,
medicinal chemistry, materials science, and environmental science.

d.Physical Chemistry

-Physical chemistry is a branch of chemistry that combines principles of physics and

chemistry to study the physical properties and behavior of matter, as well as the energy
changes that occur during chemical reactions. It focuses on understanding the fundamental
principles that govern the behavior of atoms, molecules, and chemical systems, including
topics such as thermodynamics, chemical kinetics, quantum mechanics, spectroscopy, and
statistical mechanics. Physical chemistry plays a crucial role in various scientific disciplines,
including materials science, chemical engineering, biophysics, and atmospheric chemistry.

e. Analytical Chemistry

Analytical chemistry is a branch of chemistry that focuses on the qualitative and quantitative
analysis of substances to determine their composition, structure, and properties. It involves
techniques and methods to separate, identify, and quantify chemical compounds in various
samples, such as food, pharmaceuticals, environmental samples, and more. Analytical chemists
use a range of instruments and methodologies, including spectroscopy, chromatography,
electrochemistry, and mass spectrometry, to carry out their analyses accurately and efficiently.
The results of analytical chemistry are crucial in various fields, including healthcare,
environmental monitoring, forensic science, and materials science.

f.Atoms
Atoms are the basic building blocks of matter. They are the smallest units of an element that still
retain the chemical properties of that element. Atoms consist of a nucleus, composed of protons
and neutrons, surrounded by electrons in orbitals or energy levels. Protons have a positive
charge, neutrons have no charge, and electrons have a negative charge. The number of protons in
the nucleus determines the element’s identity and is known as the atomic number. Atoms of the
same element can have different numbers of neutrons, resulting in isotopes.

g. Molecules

Molecules are formed when two or more atoms chemically bond together. These bonds can be
covalent, where atoms share electrons, or ionic, where atoms transfer electrons. Molecules can
be composed of atoms of the same element (such as O2 for oxygen) or different elements (such
as H2O for water). They can vary in size and complexity, from simple diatomic molecules like
oxygen (O2) to complex organic molecules like DNA. Molecules are the smallest unit of a
compound that retains the compound’s chemical properties.

h.Electrons

Electrons are subatomic particles that carry a negative electrical charge. They are
found orbiting the nucleus of an atom in various energy levels or orbitals. Electrons
play a crucial role in chemical bonding, as they are involved in forming chemical
bonds between atoms by either sharing or transferring electrons. They also contribute
to the overall electrical conductivity and reactivity of a substance. The number of
electrons surrounding an atom determines its chemical behavior and reactivity.

i.Protons

Protons are positively charged subatomic particles found within the nucleus of an atom. They
have a fundamental positive charge equal in magnitude to the negative charge of an electron. The
number of protons in the nucleus determines the element’s identity and is referred to as the
atomic number. Protons contribute to the overall mass of the atom and play a crucial role in
defining its chemical properties and interactions with other atoms.

j.Neutrons.

Neutrons are neutral subatomic particles found within the nucleus of an atom, along with
protons. Unlike protons, which carry a positive charge, neutrons have no electrical
charge; they are electrically neutral. Neutrons contribute to the overall mass of the atom
but do not significantly affect its chemical properties. The number of neutrons in the
nucleus can vary for a given element, resulting in different isotopes of that element.

k.Lewis Structure

A Lewis structure, named after the American chemist Gilbert N. Lewis, is a symbolic
representation of the bonding and non-bonding electron pairs in a molecule or ion. In a Lewis
structure, the chemical symbols for the atoms are used, along with dots or lines to represent the
valence electrons around each atom. Valence electrons are the outermost electrons involved in
bonding and determining the chemical properties of an atom. The Lewis structure helps in
understanding the arrangement of electrons and predicting the molecular geometry and chemical
behavior of a molecule.

l.Compounds

Compounds are substances composed of two or more different elements chemically

bonded together in fixed proportions. These elements are held together by chemical
bonds, which can be either ionic or covalent. Compounds have unique properties that
are different from the properties of their constituent elements. For example, water
(H2O) is a compound composed of hydrogen and oxygen atoms, and it exhibits
properties distinct from those of hydrogen gas (H2) and oxygen gas (O2).
Compounds can range from simple molecules like water to complex structures like
proteins and polymers.

m. elements

Elements are pure substances consisting of atoms that all have the same number of protons in
their atomic nuclei. Each element is represented by a unique chemical symbol (e.g., H for
hydrogen, O for oxygen) and is listed on the periodic table. Elements cannot be broken down
into simpler substances by chemical means. They are the fundamental building blocks of
matter and combine in various ways to form compounds and molecules. There are currently
118 known elements, each with distinct properties and characteristics.

2.What do you Expect to learn from this subject of Chemistry.

A study of chemistry can shed light on many facets of daily living and the natural world. The
following are some things you might anticipate learning about chemistry:
Understanding Matter: Studying chemistry gives you a basic understanding of the natural world,
develops your critical thinking and problem-solving abilities, and opens up career opportunities
in fields related to criminology. It also helps you understand the composition, structure,
properties, and behavior of matter, from the smallest atoms to complex molecules and materials