CHEM

chemistry

chemistry

study of matter and changes it undergoes

matter

anything that takes up space and mass

worldview

perspective from which to see and interpret life

model

workable explanation, description, or representation of an actual molecule

aphothecaries

early pharmacist in ancient chemistry

Greek philosphers

applied reasoning to think about the nature of matter

alchemist

searched for immortality through medicines

alchemy

blend of astrology and mystcism with observation and experimentation

Benjamin Rush

The first professor of chemistry in the US

modern chemistry

uses different models to interpret what we observe about the nature of matter and the changes it undergoes

world view

belive that life evolved from nonliving compounds

biblical view

living tihngs traced back to God's special Cration by His word

biblical triad

Biblical principles, biblical outcomes, biblical principles

deductive reasoning

general statements called premises to a specific conclusion

inductive reasoning

uses facts and or data and general conclusions

Qualitive data

descriptive data

Quantitative data

numerical data

experimental group

group of samples exposed to the independent variable

control group

group of samples not exposed to the independent variable

independent variable

variable that is changed

dependent variable

The outcome factor; the variable that may change in response to manipulations of the independent variable.

theory

EXPLANATION of a natural phenomenon

law

DESCRIBES a relationship between a repeating pattern of a natural phenomenon

hypothesis

suggested explanation to a scientific question

classifications of matter

pure substances and mixtures

pure substance

consist of only one type of matter

mixture

2 or more substance that are physically combined

homogenous mixture

a mixture in which the composition is uniform throughout (e.x sugar water, soda)

heterogenous mixture

a mixture in which the composition is not uniform throughout/ can take apart easily (e.x salad, pizza)

ways to seperate mixtures

filtration, distillation, decanting

filtration

used to filter bigger particles from small fluid particles

distillation

HOMOgenous mixture way to seperate, uses different boiling points

decanting

HETEROgenous mixture way to seperate, pouring less dense material onto denser material

how do we distringuish between two catergories of matter

physical and chemical property

physical property

anything that is observed or measured w/o altering a substance's chemical composition

chemical property

properties that describe how matter acts in the present

examples of physical property

malleability, density, conductivity, ductility,

examples of chemical property

reactivity, flammability, toxicity

difference between atoms. elements, and compounds

An atom is the smallest form of an element, an element is a substance that can't be broken down into smaller substances, and a compound is two or more different elements that join together.

7 diatomic elements

hydrogen, nitrogen, fluorine, oxygen, iodine, chlorine, bromine

potential energy

energy of an object due to its position or condition

kinetic energy

energy due to an object's motion

thermodynamics

study of movement and conversion of energy

conservation of mass-energy

matter and energy cannot be created nor destroyed but can be transfromed or transferred between objects

law of entropy

(high to low concentration), never decreases in a system

thermal energy

The total energy of motion in the particles of a substance

heat

flow of thermal energy

temperature

the average kinetic energy of particles in a substance

exothermic process

RELEASE energy

endothermic process

ABSORBS energy

absolute zero

a temperature of 0 kelvins, lowest point

Aristotle

Greek philosopher, continous theory of matter

Democritus

Greek Philosopher, atomism

what replaced philosophical atomism

scientific atomism

Continous theory of matter

matter could be continously subdivided without end

atomism

matter was made of seperate discrete particles

Who founded the Law of Definite Proportions?

French Chemist Joseph Proust in 1794

What does l.o.d.p say

states every compound is formed of element combined in specific ratios by mass that are unique for that compound (e.x water)

who made a new atomic model

English school teacher John Dalton

what was the new atomic model based on

experimental evidence instead of philoshopy

Law of multiple proportions

elements can combine in different ratios to form different compounds

do elements have the same mass

no, they each have different masses

why was philoshopy used during greek times

because of the lack of tech

J.J Thomson

discovered the electron, English Physicist

How did J.J. Thomson discover the electron?

cathode ray tube experiment

Hans Geiger

conducted the gold foil experiment that led to the discovery of the nucleus

who discovered the nucleus

Ernest Rutherford

who named the protons

Ernest Rutherford

measurement

comparison of an unknown quanity to a known STANDARD unit

dimensions

measurable properties. ex. length, mass, volume, time, electrical charge

what needs to happen before a dimension can be measured

there must be a unit of measure defined for that dimensions

graduated scale

the spacing of the marks on a instrument used for measuring

instrument

artifical device made for refining, extending, or substituting for human senses

what does a measurements consis of

number and a unit

unit

standard by which the scientist compares the object

Metric system

The decimal measuring system based on the meter, liter, and gram as units of length, capacity, and weight or mass. (powers of 10)

France

first european nation to adopt MMS (had kilogram and meter)

SI

International System of Units; stanard measuring system, US and 2 other countries don't use

ampere

electrical current

candela

light intensity

kelvin

temperature

kilogram

mass

meter

length

mole

number of particles (most used in science)

second

time

base unit

part of the MS multiplied by power of ten

derived units

combinations of SI base units

square meter

area

cubic meter

volume

kilogram per cubic meter

density

hertz

frequency

newton

force

pascal

pressure

joule

energy

celcius

celcius temperature

how to change size of a unit

prefix

what do we call the process by which scientists quantify their observations of their surroundings?

taking measurements

unit conversion

mechanical process to change units

conversion factor

fraction containing both original unit and equivalent value

math rule 2

The sum or difference of measured data cannot have greater precision than the least precise quantity in the sum or difference