vocabulary
if you are in the class of chemistry, you will get vocabulary that you use every leasson in chemistry class or you do practicum in the lab. in here I have 40 vocabulary, read carefully and make sure that you are have remainded this 40 vocabulary.
• free radical : An atom or molecule
with an unpaired electron. They're way reactive.
• functional group: A generic term
for a group of atoms that cause a molecule to react in a specific way. It's really
common to talk about this in organic chemistry, where you have "aldehydes,
carboxylic acids, amines" and so on.
• gamma ray : High energy light
given off during a nuclear process. When a nucleus gives off this light, it
goes to a lower energy state, making it more stable.
• geometrical isomer : isomerism
where atoms or groups of atoms can take up different positions around a double
bond or a ring. This is also called cis- trans- isomerism.
•ground state : The lowest energy
state possible for an electron.
• group: A column (the things up and
down) in the periodic table. Elements in the same group tend to have the same
properties. These are also called "families".
excess reagent : Sometimes when
you do a chemical reaction, there's some of one reagent left over. That's
called the excess reagent.
• excited state: A higher energy
level that electrons can jump to when energy
is added.
•exothermic : When a process gives
off energy (gets hot).
•family : The same thing as a
"group" (see above)
• first law of thermodynamics : The
energy of the universe is constant. It's
the same thing as the Law of
conservation of energy.
• fission : A nuclear reaction where
a big atom
breaks up into little ones. This is
what happens in nuclear power plants.
• free energy : also called
"Gibbs free energy", it's the capacity of a system to do work.
• half-life : The time required for
half of the radioactive atoms in a sample to decay. When talking about chemical
reactions, it's the amount of time required to make half the reagent react.
• half-reaction: The oxidation or
reduction part of a redox reaction.
• halogen : The elements in group
17. They're really reactive.
•heat of reaction: The amount of
heat absorbed or
released in a reaction. Also called
the "enthalpy of reaction"
• heat : The kinetic energy of the
particles in a system. The faster the particles move, the higher the heat.
• Hess's Law : The enthalpy change
for a change
is the same whether it takes place
in one big step or in many small ones.
• heterogeneous mixture: A mixture
where the substances aren't equally
distributed.
• homogeneous mixture: A mixture
that looks really "smooth" because
everything is mixed up really well.
• Hund's rule: The most stable
arrangement of electrons occurs when they're all unpaired.
• hybrid orbital: An orbital caused
by the mixing of s, p, d, and f-orbitals.
• hydration : When a molecule has
water molecules attached to it.
• hydrocarbon : A molecule
containing carbon and hydrogen.
• hydrogen bond : The tendency of
the hydrogen atom stuck to an electronegative atom to become attracted to the
lonepair electrons on another electronegative atom. It's a pretty strong
intermolecular force, which explains why water has such a high melting and
boiling point.
•ideal solution : A solution in
which the vapor pressure is directly proportional
to the mole fraction of solvent
present
• immiscible: When two substances
don't dissolve in each other. Think of oil and water.They're immiscible. Organic
compounds and water are frequently immiscible.
•indicator: A compound that turns different
colors at different pH values. We generally
like to have the color change at a pH of around seven because that's where the
equivalence point of a titration is.
• inhibitor: A substance that slows
down a chemical reaction.
• inorganic compound: Any compound
that doesn't contain carbon (except for carbon dioxide, carbon monoxide, and
carbonates).
•hydrogenation: When hydrogen is
added to a carbon-carbon multiple bond.
•hydronium ion: The H+ ion, made
famous by acids.
•hydroxide ion: The OH- ion, made
famous by bases.
• ideal gas law : PV=nRT
• ideal gas : A gas in which the
particles are infinitely small, have a kinetic energy directly proportional to the
temperature, travel in random straight lines, and don't attract or repel each
other. Needless to say, there's no such thing as an ideal gas in the real
world. However, we use ideal gases anyway because they make the math work out well
for equations that describe how gases behave.
• insoluble: When something doesn't
dissolve.
•intermediate: A molecule which
exists for a short time in a chemical reaction before turning into the product.
• intermolecular force: A force that
exists between two different molecules. Examples are hydrogen bonding (which is
strong), dipole-dipole forces (which are kind of weak), and London dispersion
forces (a.k.a. Van der Waal forces), which are very weak.
• ionic bond: A bond formed when
charge particles stick together.
•ionization energy: The amount of
energy required to pull an electron off of a gaseous atom.
