Introduction to Matter: Chapter 5: The Periodic Table Revised by: Mrs. Estevez 6 th Grade Science

Reading the Periodic Table

Who arranged the elements? Dmitri Mendeleev- Russian Chemist- 1869 Arranged in order of increasing atomic mass. Periodic- describes something that occurs or repeats at regular intervals. Periodic Law- the law that states that repeating chemical and physical properties of elements change periodically with the atomic numbers of the elements.

Columns The vertical (up and down) columns of the periodic table (there are 18) are called groups or families. Elements in the same group or family have similar chemical and physical properties.

Rows The horizontal rows of the periodic table are called periods. Elements in a period are not alike in properties. The first element in a period is usually an active solid, and the last element in a period is always an inactive gas.

Rows Atomic number (number of protons) increases from left to right across a period. Atomic mass (number of protons and neutrons) increases from left to right across a period. Metals are on the left Non-metals are on the right

What are the families?

What are metals, non-metals, and metalloids? Tend to be shiny, most are ductile and/or malleable, good conductors of heat and electrical current. Non-Metals: Not malleable or ductile, not shiny, poor conductors of heat and electrical current. Metalloids: (also called semiconductors) Properties of both metals and non-metals.

NON-METALS not able to conduct electricity or heat very well very brittle, and cannot be rolled into wires or pounded into sheets exist in two of the three states of matter at room temperature: gases (such as oxygen) and solids (such as carbon). have no metallic luster, and do not reflect light.

METALLOIDS have properties of both metals and non-metals some of the metalloids, such as silicon and germanium, are semi-conductors. This means that they can carry an electrical charge under special conditions. This property makes metalloids useful in computers and calculators

ALKALI METALS Group 1 very reactive metals because they only have 1 electron in their outer shell do not occur freely in nature (combine with other elements) malleable, ductile, good conductors of heat and electricity. softer than most other metals can explode if they are exposed to water

not found free in nature ALKLINE EARTH METALS Group 2 metals very reactive not found free in nature

TRANSITION METALS Groups 3-18 ductile and malleable, and conduct electricity and heat iron, cobalt, and nickel, are the only elements known to produce a magnetic field.

RARE EARTH ELEMENTS Top Row: Lanthanides: shiny, reactive metals. Bottom Row: Actinides: radioactive (unstable), most are made in laboratories.

Solids at room temperature Boron- metalloid Boron Group Group 13 Reactive Solids at room temperature Boron- metalloid

solids at room temperature Carbon Group Group 14 - Contains 1 non-metal, 2 metalloids, and 3 metals. Reactivity varies solids at room temperature

Nitrogen Group Group 15 Contains 2 metals, 2 non-metals, and 2 metalloids Reactivity varies Solid at room temperature, except for Nitrogen (it’s a gas)

Oxygen Group Group 16 -3 non-metals, 1 metalloid, 1 metal -reactive -All except oxygen (gas) are solid at room temperature

HALOGENS Group 17 "halogen" means "salt-former" and compounds containing halogens are called "salts" Reactive non-metals (only need 1 extra electron to complete outer shell) exist in all three states of matter: -Solid- Iodine, Astatine Liquid- Bromine Gas- Fluorine, Chlorine

NOBLE GASES Group 18 Unreactive non-metals (their outer shell is full) Colorless, odorless gasses at room temperature

Hydrogen: In a group of its own… Reactive Colorless, odorless gas at room temperature Low density Explosive reactions with oxygen