#general chem notes

[er-cryptid]

Palladium Difluoride

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[oxoanion]

GENERAL CHEM I LECTURE 2: Matter and Measurement, continued

Fundamental Units

Mass: kilogram (kg)

Length: meter (m)

Temperature: Kelvin (K)

Amount of substance: mole (mol)

Time: second (s)

Electric current: ampere (A)

Lumious intensity: candela (cd)

Any other units called derived units

Fundamental Prefixes

If you want to go up from base unit, move decimal point to the left

If you want to go down from base unit, move decimal point to the right

Common prefixes:

Deci-: 0.1, 10-1

Centi-: 0.01, 10-2

Milli-: 0.001, 10-3

Micro-: 0.000001, 10-6

Nano-: 0.000000001, 10-9

Pico-: 0.000000000001, 10-12

Deka-: 10, 101

Hecto-: 100, 102

Kilo-: 1000, 103

Mega-: 1000000, 106

Giga-: 1000000000, 109

Tera-: 1000000000000, 1012

Mass: amount of matter in an object

Weight: measures the force with which gravity pulls on a object

Conversion Factors in Temperatures

C to K = 273.13 + C

C to F = (9/5)(C + 32)

F to C = (5/9)(F - 32)

Density: mass/volume

The density of silver at 25 degrees C is 10.5g/cm3. What is the mass of a cube of silver that measures 0.84 m at each side?

Given: 10.5 gAg/1 cm3

First, convert meters to centimeters. Then, cube the answer, and convert into appropriate factors.

0.84 m = 84 cm

(84 cm)3 = 592704 cm3

592704 cm3 * 10.5 gAg/1 cm3 = 6.2 * 106 gAg

[oxoanion]

GENERAL CHEM I LECTURE 1: Matter and Measurement

Periodic Table Organization

Columns = groups

18 groups

Compares relative reactivities between elements

Rows = periods

7 periods

Compares electronic configurations between elements

Atomic number: related to the number of subatomic particles in its nucleus (number of protons + neutrons)

Different Kinds of Elements

Main Groups

Groups 1-2 ("S" block) and 13-18 ("P block")

Transition Metals

Groups 3-12

Inner Transition Metals

14 groups between 3 and 4

These are the lanthanides (elements 57-71) and actinides (90-103)

Chemical Categorization of Elements

Alkali metals: Group 1

Extremely reactive

Lithium, sodium, potassium

Alkaline earth metals: Group 2

Not as reactive as alkali metals

Magnesium, beryllium, calcium

Electron-deficient group: Group 13

Elements that tend to be reactive

Typically accept electrons

Pnictides: Group 15

Nitrogen, phosphorus

Calcogens: Group 16

Oxygen, sulfur, selenium

Halogens: Group 17

Colorful, corrosive gases

Fluorine, chlorine, bromine

Noble gases: Group 18

Have little to no reactivity

Neon, helium, krypton, xenon

Metals: left to the zigzag line on the periodic table (except hydrogen)

Nonmetals: right to the zigzag line on the periodic table (including hydrogen)

Metalloids (semimetals): lie along zigzag line (boron, silicon, germanium, arsenic)

Properties of Elements

Intensive properties: independent of sample size

Ex. temperature, melting point

Extensive properties: dependent on sample size

Ex. length, volume

Physical properties: characteristics that do not affect a sample's chemical makeup

Chemical properties: characteristics that involve a change in a sample's chemical makeup