Just The Basics of Chemistry Part 1
🧪 What is Chemistry?
First of all what is Chemistry ?
Chemistry is a branch of Science or you can call call it the Science Of Matter
It's all about composition, structure, properties, and transformations
It's used to study atoms, molecules and there connections
Some examples of it would be :
1. Water Boiling 🌡️:
Water is turning into steam
2. Dissolving Salt in Water 🧂:
Salt breaks into tiny particles and spreads throughout the water.
3. Burning Wood or Paper 🔥:
The wood and paper reacts with oxygen to form ash, smoke, and gases.
Chemists use experiments and theories to understand and manipulate matter, impacting fields
like medicine, energy, and materials. Think of it as the rulebook for how stuff in the universe
mixes, reacts, or changes.
It's also split into branches like organic (carbon-based compounds),
inorganic (metals, minerals), physical (energy and reactions), analytical
(substance identification) and biochemistry (life processes).
Basic Concepts in Chemistry 🔬
Matter
Matter is anything that has mass and occupies space. It’s the physical stuff
of the universe, made up of atoms and molecules.
Matter exists in states like solid, liquid, gas, and plasma, and it undergoes physical or chemical changes (e.g., melting, reacting).
At its core, matter is built from elements in the periodic table, with protons(+), neutrons(), and electrons(-) as the key players.
Its properties—density, conductivity, reactivity—define how it behaves.
Chemistry studies matter to understand and control these behaviors.
Atoms
Atoms are the basic building blocks of matter, consisting of a nucleus (protons and neutrons)
surrounded by electrons.
Protons carry a positive charge, electrons a negative charge, and neutrons are neutral.
The number of protons defines an element’s atomic number, while the sum of protons and neutrons gives its atomic mass.
Electrons orbit in energy levels, influencing chemical bonding.
Atoms are incredibly small, about 0.1-0.5 nanometers across, and are mostly empty space.
They combine to form molecules through bonds like covalent or ionic.
Quantum mechanics governs their behavior, with electrons existing in probabilistic orbitals rather than fixed paths.
Elements
Elements are pure substances made of atoms with the same number of protons (atomic number).
There are 118 known elements, listed in the periodic table, like hydrogen (1 proton),
oxygen (8 protons), or gold (79 protons).
Each has unique properties—metals, nonmetals, or metalloids—and forms everything from
stars to cells through bonding.
Isotopes vary in neutron count but keep the same element identity.
Compounds
Compounds are substances formed when two or more elements chemically bond in fixed ratios, like water (Hâ‚‚O) or carbon dioxide (COâ‚‚).
Bonds can be covalent (sharing electrons), ionic (transferring electrons), or metallic.
Compounds have unique properties distinct from their elements—e.g., sodium (explosive) and chlorine (toxic gas) form table salt (NaCl).
They’re broken or formed via chemical reactions.
Types of Changes in Chemistry ⚗️
Physical Change
A physical change alters a substance’s form, state, or appearance without changing its chemical composition.
Examples: ice melting (Hâ‚‚O stays Hâ‚‚O), cutting wood, or dissolving sugar in water.
No new substances form, and it’s often reversible.
Contrast with chemical changes (e.g., burning), which create new compounds.
Chemical Change
Transforms a substance into a new one with different chemical properties via reactions.
Examples: burning wood (makes ash, COâ‚‚), rusting iron. Bonds break or form, irreversible in practice. Unlike physical change, it alters molecular structure.