Chapter 1 Flashcards
Chemistry
the study of the composition, structure, and properties of matter, the processes that matter undergoes, and the energy changes that accompany these processes.
Chemical
any substance that has a definition composition
EX. sucrose, water, carbon dioxide, etc…
Applied research
Generally carried out to solve a certain problem.
Basic research
Carried out to increase knowledge, to why/how a specific reaction occurs and what the properties of a substance is.
Matter
is anything that has mass and takes up space(volume).
Atom
- the smallest unit of an element that maintains the chemical identity of that element.
- is one
Element
a pure substance that can not be broken down into simpler, stable substances and is made of one type of atom.
EX. carbon hydrogen, chlorine, etc…(periodic table)
Compound
- a substance that can be broken down into simple, stable substances and is made from the atoms of two or more elements.
- made up of molecules
- EX. sucrose(made of carbon, hydrogen, and helium)
Molecule
- the smallest unit of an element/compound that retains all of the properties of the element/compound.
- particle made of more than one atom bonded together
Property
a characteristic that defines an entire group of substances.
Physical property
a characteristic that can be observed or measured without changing the identity of the substance. EX. water freezes to make ice – melts to create water — boils — etc…
Extensive property
depends on the amount of matter that is present.
EX. volume, mass, energy
Intensive property
does not depend on the amount of matter present. EX. density, melting/boiling point, etc…
Physical change
a change in a substance that does not involve a change in the identity of the substance. EX. cutting, grinding, melting, boiling, etc…
Chemical property
relates to a substance’s ability to undergo changes that transform it into different substances. EX. charcoal burning (it combines with oxygen to become carbon dioxide gas, the original substances don’t change).
Chemical change
- a change in which one or more substances are converted into different substances.
EX. color change, odor change, production of gas/solids, and energy released/absorbed
Chemical reaction:
mercury oxide –-> mercury + oxygen
Reactants
the parts that make up a product.
a substance that takes part in and undergoes change during a reaction.
Products
substances formed by the chemical combination/change.
Endothermic
(of a reaction or process) accompanied by or requiring the absorption of heat.
Exothermic
(of a reaction or process) accompanied by the release of heat
Pure substances
- can ONLY be an element or compound
- has a fixed composition(same)
- can be broken down into two or more simple compounds
decomposing a compound
- separation by electrolysis
- separation by heating
Mixtures
- a blend of two or more kinds of matter, each which retain its own identity/properties
- simple and complex
- elements aren’t bounded
- parts of a mixture can be separated
Heterogeneous mixture
mixtures that are not uniform in the composition
different
Homogeneous mixture
mixtures that are uniform in the composition
also known as solutions
the same
EX. brass
separation a mixture
- filtration
- chromatography using a centrifuge
Groups/families
- the vertical columns on the table
- each group has similar chemical properties
- the two major categories is metals and nonmetals but also metalloids
Periods
- the horizontal rows on the periodic table
- elements that are close in the same period are usually more similar
- the two sets of elements placed below the table are called: lanthanide series and actinide series
- these are all metallic elements
placed below the table to keep it from getting too wide
Metalloids
has intermediate properties between the metals and nonmetals, a mix.
Main branches of chemistry and their differences
1) Organic chemistry; has to have carbon in it like organic molecules
EX. plastic
2) Inorganic chemistry; anything that doesn’t include carbon, molecules that aren’t carbon-based
3) Physical chemistry; learn about energy in the way of molecules and energy
EX. # of heat released, light absorbed, etc…
4) Biochemistry; all things living; dealing with living things
5) Analytical chemistry; identifying substances based on their properties, analyzing, and observing it.
6) Theoretical chemistry; when you use mathematical or computer models to explain the chemistry and show it.
EX. graphs, equations, etc…
Role of technology in chemistry and research
In chemistry, technology is basically the use of chemistry for the development of new technologies.
In research, technology makes it more efficient, accurate, and accessible. They use technology to make data collection and analysis.
How does energy change with changes in matter?
Depending on if it is a solid, liquid or gas, they are at different speeds and density.
When it is a solid, there is not as much energy because no molecules move compared to gas, the molecules have lots of energy, bouncing like crazy.
Molecular and energy differences between states of matter
Solid - fixed particles, connected in a solid form with pretty much no movement
Liquid - rapid particle movement but closer and jumbled together
Gas - can take any shape and all of the molecules bounce off of each other, always moving
Volume and shape differences between states of matter
Solid
Liquid
Gas
How to classify matter
Pure substances:
can ONLY be an element of a compound
Mixtures:
a blend of two or more kinds of matter, each which retain its own identity/properties
How is the periodic table set up/arranged
It is set up in groups/families and periods.
Groups/families:
vertical columns that help categorize it into metals, nonmetals, and metalloids. Also help put together elements with similar chemical properties. Periods:
the horizontal rows that have similar trends.
Proprties of Metals
an element that is a good electrical and heat conductor
has malleability; can be hammered or rolled into thin sheets
is ductile; can be draw into a fine wire
has tensile strength; ability to resist breaking when pulled
most are silver/grayish white except; gold and copper
EX: iron, titanium, aluminum, copper, nickel, etc…
Properties of Nonmetals
- an element that is a poor conductor of heat and electricity
- brittle
- some are noble gases; usually unreactive
- solid nonmetals: carbon, phosphorus, selenium, sulfur, and iodine
- liquid nonmetals: bromine
