Studied by 4 people
Chemistry
The science that deals with the composition, structures, and properties of matter and how matter changes under different conditions.
Organic chemistry
The study of substances that contain carbon, which allows them to burn.
all living things contain what?
Carbon
Inorganic chemistry
The study of substances that do not contain carbon but may contain hydrogen.
Matter
Anything that has mass and takes up space
what properties matter have?
physical and chemical
matter can exist as either
solid, liquid or gas
Elements
simplest form of matter
Elements are composed how many parts/unit?
one
Elements cannot be what?
broken down
How many elements are there?
118
how many elements a naturally occuring?
98
Atoms
The particles from which all matter is composed.
Molecules
two or more atoms joined together
Elemental molecule
a chemical combination of atoms of the SAME element.
Compound molecule
Chemical combination of two or more atoms from DIFFERENT elements
compound molecule is also known as
compounds
states of matter
solid, liquid, gas
Soilds
Have a definite shape, volume, and weight
liquid
have a definite volume and weight but not a definite shape
Gases
No definite shape or volume
physical properties
those characteristics determined without a chemical reaction; do not cause a chemical change in the identity of a substance.
chemical properties
Those characteristics that can only be determined with a chemical reaction and cause a chemical change in the identity of a substance.
Physical Change
A physical change changes the form without forming a new substance.
chemical change
A chemical change is a change in a substance's chemical composition. A chemical change creates new substances with different properties.
chemical compound
a combination of two or more atoms of DIFFERENT elements united chemically with a fixed chemical composition, definite proportions, and distinct properties.
Physical mixtures
Combination of two or more substances that are united physically, in any proportions with combined properties.
Hydrogen (H)
A colorless, odorless, tasteless gas and is the lightest element known; found in chemical combination with oxygen in water and other elements in most organic substances; flammable and explosive when mixed with air.
Oxygen (O)
The most abundant element found on earth; is a colorless, odorless, tasteless gas; comprises about half of the Earth's crust; half of the rock; one-fifth of the air, 90% of the water; combines with other elements to form an infinite variety of compounds, called oxides. It supports combustion.
Nitrogen (N)
Colorless, gaseous elements; makes up about four-fifths of the air and is found chiefly in the form of ammonia and nitrates.
Air
The gaseous mixture that makes up the Earth's atmosphere
Water (H2O)
The most abundant of all substances, comprising about 75% of the Earth's surface and 65% of the human body.
hydrogen peroxide (H2O2)
A colorless liquid with a characteristic odor and slightly acid taste; used in hair color and as an antiseptic.
Potential Hydrogen stands for?
pH
the lower case p in pH represents?
quantity
the upper case H in pH represents
hydrogen ion
Potential Hydrogen (pH)
indicates the relative degree of acidity or alkalinity of a substance.
if its below a 7 on the pH scale its?
acidic
if its above a 7 on the pH scale its?
alkaline
if its 7 on the pH scale its?
neutral
the pH scale goes from what to what?
0 to 14
the pH scale is what? meaning what?
logarithmic, meaning a change of one whole number represent a tenfold change in pH. A change of two whole numbers, represents a change of ten times 10.
Logarithm
multiples of ten
Ion
An atom or group of atoms that has a positive or negative charge.
Ionization causes
an atom or molecule to split in two, creating a pair of ions with opposite electrical charges.
Anion
A negatively charged ion
Cation
A positively charged ion
Hydrogen ion (H+) is?
acidic
Hydroxide ion (OH-)
alkaline
what does a solution need to have a pH?
water, without water, there is no pH.
acid mantle
Skin produces both sebum and sweat to create a protective barrier, known as the acid mantle, against bacteria, weather, and pollution; instrumental in the renewal process.
Acid-alkali neutralization reactions
The same reaction that naturally ionizes water to create hydrogen (H+) ions and hydroxide ions (OH-) are mixed together in equal proportions, they neutralize each other to form water (H2O).
Oxidation-Reduction (Redox)
A chemical reaction in which the oxidizing agent is reduced and the reducing agent is oxidized.
what is another word for oxidation reduction?
redox
Oxidizing agent
A substance that releases oxygen. Redox reactions are always an exchange. When a substance is oxidized, the oxidizer is always reduced.
reduction
The subtraction of oxygen or the addition of hydrogen.
Oxidation
Can take place without oxygen; can occur when hydrogen is subtracted from a substance or oxygen is added.
Combustion
Rapid oxidation of a substance, accompanied by the production of heat and light.
Antioxidants
Used to stabilize skin care products by preventing oxidation that would otherwise cause a product to turn rancid and decompose.
Solutions, suspensions, emulsions all contain?
two or more different substances.
Solution
A stable uniform blend of two or more mixable substances. They do not separate.
solute
The dissolved substance in a solution
Solvent
The substance, usually liquid, which dissolves another substance to form a solution, with no change in chemical composition.
What is the universal solvent?
water
Miscible liquids
Liquids that can mix together without seperating
Immiscible liquids
liquids not capable of being mixed.
Suspension
An unstable mixture of undissolved particles in a liquid.
suspensions are unstable and do what over time?
separate
Emulsion
An unstable mixture of two or more immiscible substances united with the aid of a binder or emulsifier.
emulsify
to form an emulsion
Emulsifier
An ingredient that brings two normally incompatible materials together and binds them into a uniform and fairly stable blend.
Surfactants
Substances that act as a bridge to allow oil and water to mix, or emulsify.
Head of the surfactant is
hydrophilic
tail of the surfactant
lipophilic
Hydrophilic is the
head
lipophilic is the
tail
Oil in water emulsion (O/W)
oil droplets emulsified in water.surrounded by water.
Water-in-oil emulsion (W/O)
water droplets are suspended in an oil base surrounded by oil.
pure substance
A chemical combination of matter in definite (fixed) proportions.
miscible
capable of being mixed
Immiscible
cannot be mixed
emulsions are a special type of suspension because?
they can separate but over a long period of time.
suspension particles are
large
solution particles are
small
hydrophilic
capable of combining with or attracting water. (water loving)
lipophilic
Having an affinity for or an attraction to fat and oils (oil-loving).
if the tail is pointing out in an emulsion it is a?
water in oil emulsion.
if the tail is pointing in, in an emulsion it is a?
oil in water emulsion.
volatile alcohols
evaporate quickly and easily; for example, rubbing alcohol (isopropyl) and hairsprays (ethyl alcohol).
Alkanolamines
Used to neutralize acids or raise the pH.
Ammonia
Colorless gas with a pungent odor that is composed of hydrogen and nitrogen.
Glycerin
Sweet, colorless, oily substance used as a solvent and as a moisturizer in skin and body creams.
Silicones
Special type of oil used in hair conditioners, water-resistant lubricants for the skin, and nail polish dryers.
Volatile Organic Compounds (VOCs)
Contain carbon (organic) and evaporate very easily (volatile)
Overexposure
Prolonged, repeated, or long-term exposure that can cause sensitivity.
Alpha hydroxy acids (AHAs)
are used to exfoliate the skin and helps adjust the ph of a lotion or cream
Thioglycolic acid
A colorless liquid or white crystals with a strong unpleasant odor that is used in permanent waving solutions.
Alkalis
Also known as bases; compounds that react with acids to form salts.
Sodium Hydroxide
commonly known as lye, is a very strong alkalis (base) used in chemical relaxers, callous softeners, and drinking cleaners.
exothermic reaction
A reaction that releases energy in the form of heat
Note
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