GenChem PPT

chemistry

study of matter

matter

anything that occupies space and has mass

• composition

• structure

• changes that matter undergoes

• energy involved in such changes or interactions

these 4 are all under matter

weight

measure of force that is equal to the gravitational pull on an object

pure substance

single kind of matter that cannot be separated into other kinds of matter by any physical means

element

simplest form of matter; 1 kind of material or atom

compound

substances composed of two or more elements united chemically in definite proportion

mixture

• composed of 2 or more substances that are not chemically combined

• 2 or more substances wherein individual substance identities are retained and can be separated by physical means

solid

• state of matter where it has definite shape and volume

• non-compressible

• molecular motion - vibrates

liquid

• state of matter where it has indefinite shape but definite volume

• molecular motion - glides

gas

• state of matter where it has indefinite shape and volume

• molecular motion - constant random

plasma / ionized gas

• most abundant state of matter and the 4th one

• has p+ and e- (greatly affected by magnetic field)

homogenous mixture

this class of mixture has a uniform composition and appearance (1 phase)

heterogenous mixture

this class of mixture comprises of two or more substances that can be distinctly observed and even separates easily (2+ phases)

mleting

its other names are fusion, liquefaction, & thawing

Antoine Lavoisier

the law of conservation of mass was by _____

law of conversation of mass

total mass of all products of a chemical reaction is equal to the total mass of all reactants of that reaction

mass / matter

constant of law of conservation of mass

law of definite proportions / Proust’s law

a chemical compound always contains exactly the same proportion of elements by mass

law of multiple proportions

when two elements form a series of compounds, the ratio of the masses of the 2nd element combined with 1 gram of the first element can always be reduced to the smallest whole number

law of multiple proportions

when chemical elements combine, they do so in a ratio of small whole numbers

law of combining weight

when two elements combine with each other to form more than one compound, the weights of one element that combine with a fixed weight of the others are in a ratio of small whole numbers

proton

• positive (+) subatomic particle

• the atomic number in the periodic table

electron

• negative (-) subatomic particle

• equal to the no. of protons in an uncharged atom

• negligible weight (1,836 more lighter than p+)

J.J. Thomson

he discovered the electron

Robert Andrews Millikan

he performed the oil drop experiment to measure accurate charge and mass of e-

neutron

• no charge

• discovered by James Chadwick

• atomic mass when combined with p+