Week 1-3: College Chemistry

John Dalton

English chemist and physicist who formulated atomic theory and the law of partial pressures

What did J.J. Thomson determine about the atoms?

Charge to mass ratio, they must contain electrons, and they MUST contain positive charges

Robert Millikan

1909 oil drop experiment, calculated the charge of the electron, calculate the mass of electrons

What did Ernest Rutherford discover in 1909?

Atomic nucleus and proposed a nuclear model of the atom

What experiment did Ernest Rutherford conduct with gold foil?

Gold foil experiment - fired negative ions at thin sheet of gold foil

James Chadwick

Discovered the neutron

Who discovered the law of conservation of mass?

Antoine Lavoisier

How did Antoine Lavoisier define an element?

As a basic substance that could not be further broken down by the methods of chemistry

Democritus

Greek philosopher that said all matter is made of tiny particles called "atomos" or atoms

What is the conversion factor between inches and centimeters?

1 in = 2.54 cm

How many feet are in a mile?

1 mi = 5280 ft

How many pounds are in a kilogram?

1 kg = 2.2 lbs

How many liters are in a gallon/conversion factors between them?

1 gal = 3.785 L

Ionic bonds are formed when

electrons are completely transferred from one atom to another

Covalent bonds form when

electrons are shared between two atoms

chemical change

A change in which one or more substances combine or break apart to form new substances.

What happens during a chemical change?

Substances combine or break apart to form new substances.

physical property

A characteristic of a pure substance that can be observed without changing it into another substance

characteristics of a solid

Definite shape and volume

characteristics of liquids

A state of matter that has no definite shape but has a definite volume.

characteristics of a gas

A state of matter with no definite shape or volume

Covalent prefixes

mono, di, tri, tetra, penta, hexa, hepta, octa, nona, deca

How many periods and groups are on the periodic table?

7 periods and 18 groups

Celcius to Kelvin

K = C + 273

Celcius to Fahrenheit

F = 1.8C + 32

Density equation

mass/volume

empirical formula

a formula with the lowest whole-number ratio of elements in a compound

molecular formula

shows the types and numbers of atoms combined in a single molecule of a molecular compound

What is an ion and what charges can it have?

a charged atom or molecule that can be negative (anion) or positive (cation) depending on whether it lost or gained electrons