chem ch. 1-3

chemistry

chemistry

the study of the composition, structure, and properties of matter, the processes/changes that matter undergoes, and the energy changes that accompany these processes

branches of chemistry

organic chemistry - the study of things from living things (organic = carbons bonded to other carbons)

inorganic chemistry - the study of the properties and behavior of inorganic compounds (including metals, minerals, and organometallic compounds)

physical chemistry - the study of the behavior of matter; starts to get into physics

analytical chemistry - looking at smth and figuring out what it is

biochemistry - the study of chemical processes relating to organisms

theoretical chemistry - tries to explain data and make predictions

matter

any substance that has mass and occupies space (stuff); made of elements

mass

the measure of the amount of matter (stuff); does not change; measured in g or kg

weight

the force of gravity acting on a mass; differs based on amount of gravity; measured in N or lbs

atom

the smallest unit of an element that maintains its chemical identity; differentiated by chemical/physical and intensive/extensive properties; can’t be cut further without nuclear power and losing its properties/composition

element

a pure substance that cannot be broken down into simpler, stable substances and is made of a single type of atom

compound

a substance that can be broken down into simple, stable substances; composed of two or more types of atoms

molecule

two or more of any kind of atom stuck together (all compounds are molecules but not all molecules are compounds)

intensive properties

properties that do not depend on amount (ex. density, melting/boiling point)

extensive properties

properties that depend on amount (ex. mass, volume)

physical property

can be measured/observed without changing the identity of the substance (without a chemical reaction); ex. boiling/melting point, density (could look like a chemical reaction: salt dissolving in water)

chemical property

how a substance changes in a chemical reaction; flammability, reactivity (rusting)

physical change

a change in a substance that does not change the identity of the substance (ex. phase change, dissolution)

chemical change

a change in the identity of a substance as the result of a chemical reaction (ex. oxidation, fermentation, decomposition)

solid

particles packed closely, often rigidly bonded to each other; definite shape/volume

liquid

particles closely packed but able to slide past each other; indefinite shape (takes shape of container because molecules can move), definite volume (not compressible)

gas

particles far apart/able to shoot around freely; indefinite shape/volume (compressible)

plasma

superheated gas stripped of its electrons

pure substance

a substance made of the same atoms/molecules that are chemically bonded and can’t be physically separated

mixture

matter consisting of two or more physical substances that retain their individual identities and are not chemically combined (can by separated by physical means)

homogeneous

a mixture that has a uniform composition and properties throughout; also called a solution

heterogeneous

a mixture without uniform composition and properties throughout

solution

a homogeneous mixture of one or more solutes dissolved in a solvent

phase

the states in which matter can exist; determined by how tightly molecules are packed; state changes occur with temperature changes and therefore the increase/decrease of energy

chemical

n. any substance with a defined composition

adj. relating to chemistry or the interactions of substances as studied in chemistry

importance of 6.02 × 10^23

6.02 ×10^23 hydrogen atoms is 1.008 amu (atomic mass)

rows on periodic table

periods

columns on periodic table

groups

what is the exception to the left side of the stair-step being all metals

hydrogen

why is hydrogen in the alkali metals

it reacts the same in chemical reactions

what direction is more reactive in alkali earth metals

down

what direction is more reactive in hallogens

up

why were lanthanides and actinides moved

so the table fits on one page

state of metals/non-metals/metalloids

metals

• solids at room temp (except for mercury: liquid)

non-metals

• some gases at room temp

• some solids at room temp

• one liquid at room temp (bromine)

metalloids

• solids at room temp

appearance of metals/non-metals/metalloids

metals

• shiny luster

non-metals

• not very shiny

metalloids

• can be shiny or dull

conductivity of metals/non-metals/metalloids

metals

• good conductors of heat/electricity

non-metals

• poor conductors of heat/electricity

metalloids

• may conduct heat/electricity

malleability and ductility of metals/non-metals/metalloids

metals

• malleable

• ductile

non-metals

• brittle

• not ductile

metalloids

• brittle

• not ductile

precision

the closeness of a set of measurements (consistency)

accuracy

the closeness of a set of measurements to the correct or accepted value

metalloids on periodic table

silicon, germanium, arsenic, antimony, tellurium

ASTAG