Chemistry test 1-2

early chem

embalming fluids, production of metal

Greeks

four elements: water, fire, air, earth and alchemy

Georg Baur

developed systematic metallurgy

Robert Boyle

preformed experiments to measure relationship between the pressure and volume of air

17th and 18th century

interest in combustion. Georg Stahl suggested phlogiston flowed out of burning material (false)

Joseph Priestley

discovered that oxygen supported combustion

Antoine Lavoisier

father of chem, las of conservation of mass, combustion involves oxygen and life process involves oxygen similarly

law of conservation of mass

mass is neither created nor destroyed in a chemical reaction

Joseph Proust

law of definite proportion

law of definite proportion

given compound always contains exactly the same proportion of elements by mass

Jhon Dalton

suggested that elements were composed of tiny individual particles called atoms which can’t be divided into smaller particles (solid sphere model) , a given compound always contains the same combination of atoms, and the law of multiple proportions

law of multiple proportions

when two elements form a series of compounds the ratios of the masses of the second element that combine with one gram of the first element they can always be reduced to small whole numbers

Gay Lussac

measured volumes of gases react with each other under same temperature and pressure

Amedeo

Avogadro’s hypothesis , at the same temperature and pressure, equal volumes of different gasses contain same number of particles

JJ Thompson

studied electric discharge using cathode ray tubes, postulated the existence of negatively charged particles (electrons), determined the charge-to-mass ratio, and created the plum pudding model

Cathode ray tube experiment

ray was produced at the negative electrode and was repelled by negative pole because of the same charge

plum pudding model

spherical cloud of positive charge and electrons randomly embedded in it

Robert milkman

oil drop experiment, discovered mass of electron

Oil drop experiment

drops of oil from the atomizer became charged and using two charged plates and gravity the rate of droplets was controlled and calculated

Henri Becquerel

discovered radioactivity and types, gamma- high energy light, beta- high speed electron and alpha- particles with e 2+ charge

Ernest Rutherford

carried out an experiment on plum pudding named gold foil experiment and created a nuclear atom with positively charged nucleus

Gold foil experiment

some particles passed through, some reflected and some refracted proving that there is a dense positively charged nucleus

Daltons atomic theory

each element is made up tiny particles called atoms (true) atoms of a given element are identical (false) chemical compounds are formed when atoms of different elements combine with each other (true) chemical reactions involve reorganizations of atoms (true)

Covalent bonds

share electrons

ionic bonds

oppositely charged particles attract to on another

periods

horizontal

family/groups

vertically

group 1A

+1 charge, alkali metals

group 2A

+2 charge, alkaline earth metals

group 7A

-1 charge, Halogens

group 8A

0 charge, noble gasses

Transition metals

solve for charge except, Ag⁺¹ Zn⁺² Cd ⁺² Al⁺³

Mercury (I)

Hg₂²⁺

OH^-

Hydroxide

CN^-

Cyanide

ClO₂^-

Chlorite

Acetate

C₂H₃O₂^-

permanganate

MnO₄

CrO₄^-2

Peroxide

O₂ ^-2

per-

four oxygens

HCl

Hydrochloric acid

HClO

hydrichlorus acid

H₃PO₄

phosphoric acid

H₃ PO₃

Phosphorous acid

-ates (not included: oxygen or fluorine)

3 or 4 oxygens depending on where it is

-ites (not included: oxygen, fluorine or carbon)

3 or 2 oxygens depending on where it is

Charges for -ates and -ites

normal except period two is shifted down two