Chemistry is the scientific study of the properties and behavior of matter.[1] It is a natural science that covers the elements that make up matter to the compounds composed of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during a reaction with other substances.
In the scope of its subject, chemistry occupies an intermediate position between physics and biology.[6] It is sometimes called the central science because it provides a foundation for understanding both basic and applied scientific disciplines at a fundamental level.[7] For example, chemistry explains aspects of plant growth (botany), the formation of igneous rocks (geology), how atmospheric ozone is formed and how environmental pollutants are degraded (ecology), the properties of the soil on the moon (cosmochemistry), how medications work (pharmacology), and how to collect DNA evidence at a crime scene (forensics).
Chemistry addresses topics such as how atoms and molecules interact via chemical bonds to form new chemical compounds. There are two types of chemical bonds:
Primary chemical bonds, such covalent bonds, in which atoms share one or more electron(s); ionic bonds, in which an atom donates one or more electrons to another atom to produce ions (cations and anions); metallic bonds
Secondary chemical bonds, such as hydrogen bonds; Van der Waals force bonds; ion-ion interaction; ion-dipole interactions.
The word chemistry comes from a modification during the Renaissance of the word alchemy, which referred to an earlier set of practices that encompassed elements of chemistry, metallurgy, philosophy, astrology, astronomy, mysticism and medicine. Alchemy is often seen as linked to the quest to turn lead or other base metals into gold, though alchemists were also interested in many of the questions of modern chemistry.[8]
The modern word alchemy in turn is derived from the Arabic word al-kīmīā (الكیمیاء). This may have Egyptian origins since al-kīmīā is derived from the Ancient Greek χημία, which is in turn derived from the word Kemet, which is the ancient name of Egypt in the Egyptian language.[9] Alternately, al-kīmīā may derive from χημεία 'cast together'.[10]
The current model of atomic structure is the quantum mechanical model.[11] Traditional chemistry starts with the study of elementary particles, atoms, molecules,[12] substances, metals, crystals and other aggregates of matter. Matter can be studied in solid, liquid, gas and plasma states, in isolation or in combination. The interactions, reactions and transformations that are studied in chemistry are usually the result of interactions between atoms, leading to rearrangements of the chemical bonds which hold atoms together. Such behaviors are studied in a chemistry laboratory.
The chemistry laboratory stereotypically uses various forms of laboratory glassware. However glassware is not central to chemistry, and a great deal of experimental (as well as applied/ind
1. CHEMISTRY
•the science that deals with the
properties, composition, and structure
of substances (defined as elements and
compounds), the transformations they
undergo, and the energy that is released
or absorbed during these processes
7. SOLID
•In a solid, particles are packed tightly
together so they don't move much.
The electrons of each atom are
constantly in motion, so the atoms
have a small vibration, but they are
fixed in their position. Because of
this, particles in a solid have very low
kinetic energy.
8. LIQUID
•In a liquid, the particles are more
loosely packed than in a solid and
are able to flow around each other,
giving the liquid an indefinite shape.
Therefore, the liquid will conform to
the shape of its container.
9. GAS
• In a gas, the particles have a great deal of
space between them and have high
kinetic energy. A gas has no definite shape
or volume. If unconfined, the particles of
a gas will spread out indefinitely; if
confined, the gas will expand to fill its
container. When a gas is put under
pressure by reducing the volume of the
container, the space between particles is
reduced and the gas is compressed
10.
11. PLASMA
• Plasma is not a common state of matter here
on Earth, but it may be the most common
state of matter in the universe, according to
the Jefferson Laboratory .Stars are
essentially superheated balls of plasma.
• Plasma consists of highly charged
particles with extremely high kinetic
energy. The noble gases (helium, neon,
argon, krypton, xenon and radon) are
often used to make glowing signs by
using electricity to ionize them to the
plasma state.
12. Bose-Einstein
condensate (BEC)
• The Bose-Einstein condensate (BEC) was created by
scientists in 1995. Using a combination of lasers
and magnets, Eric Cornell and Carl Weiman, scientists at
the Joint Institute for Lab Astrophysics (JILA) in Boulder,
Colorado, cooled a sample of rubidium to within a few
degrees of absolute zero, as Live Science has previously
reported. At this extremely low temperature, molecular
motion comes very close to stopping. Since there is
almost no kinetic energy being transferred from one atom
to another, the atoms begin to clump together. There are
no longer thousands of separate atoms, just one "super
atom.
13. • A BEC is used to study quantum mechanics on a
macroscopic level. Light appears to slow down as it
passes through a BEC, allowing scientists to study the
particle/wave paradox. A BEC also has many of the
properties of a superfluid, or a fluid that flows without
friction. BECs are also used to simulate conditions that
might exist in black holes.
14.
15. FERMIONIC CONDENSATE
• Fermionic condensates are attained at lower temperatures than Bose–
Einstein condensates. Fermionic condensates are a type of superfluid. As
the name suggests, a superfluid possesses fluid properties similar to those
possessed by ordinary liquids and gases, such as the lack of a definite shape
and the ability to flow in response to applied forces. However, superfluids
possess some properties that do not appear in ordinary matter. For
instance, they can flow at high velocities without dissipating any energy—
i.e. zero viscosity. At lower velocities, energy is dissipated by the formation
of quantized vortices, which act as "holes" in the medium where
superfluidity breaks down. Superfluidity was originally discovered in liquid
helium-4 whose atoms are bosons, not fermions.
16.
17. FERMION
•A fermion is a category of
elementary particles. They are
very small and very light.
Fermions can be thought of as
the building blocks of matter
because atoms are made up of
fermions. Paul Dirac named
them fermions in honor of the
famous scientist Enrico Fermi.
18. PHYSICAL PROPERTIES
•Physical properties are
characteristics that scientists can
measure without changing the
composition of the sample under
study, such a mass, color, and
volume (the amount of space
occupied by a sample).
20. PHYSICAL CHANGE
•Physical changes are changes in which no chemical
bonds are broken or formed. This means that the same
types of compounds or elements that were there at the
beginning of the change are there at the end of the
change. Because the ending materials are the same as
the beginning materials, the properties (such as color,
boiling point, etc) will also be the same. Physical
changes involve moving molecules around, but not
changing them.
21. •Changes of state (changes
from a solid to a liquid or
a gas and vice versa)
• Separation of a mixture
• Physical deformation
(cutting, denting,
stretching)
• Making solutions (special
kinds of mixtures)
22. CHEMICAL CHANGE
• Chemical changes occur when
bonds are broken and/or formed
between molecules or atoms. This
means that one substance with a
certain set of properties (such as
melting point, color, taste, etc) is
turned into a different substance
with different properties. Chemical
changes are frequently harder to
reverse than physical changes.
23. ASSIGNMENT
LIST ATLEAST 10 SUBSTANCES THAT
YOU CAN SEE IN YOUR HOUSE AND
TRY TO WRITE ITS CHEMICAL
FORMULA.
