Chemistry H fist sem overview

Matter

Anything that has mass and takes up space (solid, liquid, gas, plasma)

Law of conservation of mass/matter/energy

Matter cannot be created or destroyed, only can change form

Mass

The measure of the amount of matter in an object (Units: g, mg, kg)

Solids

Definite shape, definite volume, temp effect: expands slightly

Liquid

Indefinite shape, definite volume, temp effect: expands more

Gas

Indefinite shape, indefinite volume, temp effect: expands alot

Gas vs. Vapor

Gases are usually gas state at room temp, Vapors are usually solid/liquid at room temp

Melting/freezing

Occurs when Solid←→Liquid, both occur at 0^.C

Boiling/Condensation

Occurs when Liquid←→Gas, both occur at 100^.C

Sublimation

Solid→Gas

Physical properties

observable with senses/can be determined without destorying the object: mass, length, color

Chemical properties

Indicates how something reacts (or doesn’t) with something else: flammability, reactivity

Extensive properties

depend on the amount of matter present; mass, heat

Intensive properties

Does not depend on the amount of matter present; color, temp

Physical changes

A change in matter that does not involve a change in the composition of individual substances; melting ice

Chemical change

A change in matter that does include a change in the composition of the substance; burning

Pure substance

Matter with the same composition throughout; element or compound

Mixture

A combo of two or more substances in which each substance keeps its unique set of properties. Can be separated into two or more pure substances

Elements

simplest form of matter that cannot be broken down any smaller

Compounds

Chemical combo of two or more elements joined together in a fixed proportion

Homogeneous mixtures (Solutions)

A mixture that has one phase, uniformed, ex: salt water, evenly distrubuted

Heterogeneous mixtures

Mixture with multiple phases, individual substances can clearly be seen in the mix, not uniformed, ex: candy salad

Signs of a chemical reaction

Color change, odor change, energy change, gas produced (bubbling), precipitate formed (solid).

Reactants

starting materials

Products

substance formed

Endothermic

Energy is lost/given off; feels warmer on the outside

Exothermic

Energy is gained/taken in; it can feel colder outside

Solute

Substance being dissolved (initial)

Solvent

the substance doing the dissolving; universal: water

solution

homogeneous mixture

Alloy

a solid solution usually made up of two or more metals; brass, bronze

periods/series

horizontal rows

groups/families

vertical columns

Metals

Left of stair step, conduct heat and electricity well, high luster, malleable, ductile, generally solid at room temp

Nonmetal

Right of stair step, don't conduct heat and electricity well, lack luster, brittle, when solid, many are gases at room temp

Metalloids

Along/touching the stair step, have properties of both groups, some are semiconductors, the elements are B, Si, Ge, As, Sb, Te, Po, At

Qualitative

Descriptive words

Quantitative

Measured, numeric

Length/Distance

Meter, m, straight line distance between two points

Mass

gram, g, amount of matter in a structure

Time

Seconds, s, intervals between two events

Temperature

Kelvin, K, relative hotness or coldness of an object; relative heat content of an object

Amount of substances

mole, mol

Light

Candela, cd, measure of luminous intensity

Electricity

Ampere, A, the rate of electron flow or current through an electrical conductor

Kilo-

k, value 1000, 1×10³

base unit

in between kilo and deci

deci-

d, 0.1, 1×10^-1

centi-

c, 0.01, 1×10^-2

milli-

m, 0.001, 1×10^-3

micro-

M, 0.000001, 1×10^-6

Nano-

n, 0.000000001, 1×10^-9

Volume

liter, L, amount of space an object takes up

Force

Newton, N, a push or pull

weight

newton, N, measure of the pull of gravity of an object

energy

joule, J, capacity to do work

Heat

Joule, J, form of energy that flows from areas of high temp to low temp

density

mass/volume, symbols: kg/m³, g/L, g/nL, g/cm³, ratio of the massof an object to its volume.

mass

amount of matter in a substance

weight

measure of the pull of gravity on an object

Density

a physical property, it depends on the type of matter, D=m/v

mL

Cm_³

L

dm³

Accurate

the closeness of a measurement to the true or accepted value

Precision

The reproductability of a set of measurements, the closeness of a set of measurements, each done the same way, to eachother

percent error

a quantitative analysis of the accuracy of your data, theretical-experimental divided by theoretical x100=%

sig figs

The purpose of sig figs is to show precision of measurements

Democritcus

All matter was made of ultimate particles- atomos

Dalton

First Atomic theory, solid atom- tiny indivisible particle (sphere)

Thomson

Discovered electron, (studied cathode ray tube), plum pudding atom- a sphere of positive matter in which electrons are embedded, discovered isotopes

Milikan

Oil drop experiment, discovered charge and mass of electrons

Rutherford

Gold fol experiment, nuclear atom

Daltons atomic theory

all matter is made up of atoms

atoms of the same element are the same

atoms of different elements are different

in a chemical reaction atoms can only be rearranged

atoms of different elements combined chemically in definite proportions to form compounds

Protons

found in nucleus, +1 charge, mass of 1 amu

neutrons

Found in nucleus, no charge, mass of 1 amu

electrons

found in electron cloud, -1 charge, mass of 0 amu

Isotope

atoms of the same element that are chemically the same and have different masses

mass number

the mass number identifies the isotope

atomic mass

average of all isotopes of an element

Cation

positive ion

Anion

Negative ion

Ionic compounds

do not exist in nature as independent molecules, exist as crystals made up of formula units

molecular compound

usually a metalloid w/ a nonmetal or two exist in nature as independent molecules, represent by molecular forms

Diatomics

Have no fear of ice cold beer, H_2, N2,F2,I2,Cl2,Br2

Hydrate

a compound in which there is a specific ratio of water molecules to formula unit of ionic compound

acid

a compound that begins with H and is dissolved In water

acids for ide

hydro—-ic acid

acids for ate

—-ic acid

acids for ite

—-ous acid

mole

the number of particles equal to the number of atoms in exactly 12 grams of carbon -12

avagadro’s number

6.02×10²³ particles

states symbols

solid- s, liquid-l, gas-g,aqueous-aq (dissolves in water)