# Periodic Table Design.

## Presentation on theme: "Periodic Table Design."— Presentation transcript:

Periodic Table Design

The Man Behind the Table
Dmitri Mendeleev 1. Russian Chemist 2. Organized the 1st Periodic Table 3. In the mid-1800’s 4. Only 63 known elements at that time 5. Predicted existence of several unknown elements 6. Element 101 is named after him

Organizing the Table Mendeleev’s Organization:
1. He put each elements information on a card. A. Atomic mass, density, color, melting point B. Valence electrons (outer-shell) 2. He saw a “periodic” pattern when arranged by atomic mass…

Mendeleev’s Table Mendeleev’s table was designed so that the elements were arranged in order of increasing atomic mass. He said, “the properties of the elements were periodic functions of their atomic masses.” However, Mendeleev was sort-of wrong!

Today’s Periodic Table
British scientist, Henry Moseley saw errors in Mendeleev’s table in 1914. Moseley rearranged the table by increasing atomic number (# of protons). Moseley’s table is the table that we use today! Henry G.J. Moseley Determined the atomic numbers of elements from their X-ray spectra (1914) Arranged elements by increasing atomic number Killed in WW I at age 28 (Battle of Gallipoli in Turkey) H.G.J. Moseley ( ) while doing post-doctoral work (with Ernest Rutherford) bombarded X-rays at atoms in increasing number and noted that the nuclear charge increased by 1 for each element. This gave him the idea to organize the elements by increasing atomic number. Periodic law – elements organized by increasing atomic number on periodic table (1913) In 1913, Moseley analyzed the frequencies of X -rays emitted by the elements and discovered that the underlying foundation of the order of the elements was atomic number, not atomic mass. Moseley hypothesized that the placement of each element in his series corresponded to its atomic number Z, which is the number of positive charges (protons) in its nucleus. Moseley- wavelengths in X-rays determined by the number of protons in the nucleus of the anode atoms - change anode, change wavelength

Review: Periodic Table GROUPS
The columns of the Periodic Table are called groups (or families) Elements in a group/family have similar properties just like how your family members have similar traits! Each group/family has a name (like your last name)

Review: Periodic Table GROUPS
The number of the group (in the ones place) indicates the number of valence electrons that atoms within that group have (or the number of the TALL column) Valence electrons are electrons located in the outermost energy level that play a role in bonding and reactivity There are 18 groups on the Periodic Table On p.11, number the GROUPS on your Periodic Table Label them “Groups/Families” with an arrow showing which direction they go.

Review: Periodic Table PERIODS
The rows of the Periodic Table are called periods Elements in a period have different properties! The periods follow a periodic pattern Periodic: occurring at regular intervals

Review: Periodic Table PERIODS
The number of the period indicates the number of energy levels that atoms within that period have There are 7 periods on the Periodic Table (Helpful fact: “Periods” has 7 letters) On p.11, number the periods on your Periodic Table Label them “Periods” with an arrow showing which direction they go.

The Table A Family or Group A Period

Metals Good conductors of heat and electricity
Usually solid at room temperature Exception: Mercury is a liquid at room temperature. On p.11, outline Mercury (Hg) in blue Malleable and ductile Located to the left of the stair-step line. On p.11 label the left half of the Periodic Table “Metals.” Exception: Hydrogen is not a metal, but is located to the left of the stair-step line. Tend to give up electrons in chemical reactions

The Metals

Group 1: Alkali Metals Alkali Metals

Group 2: Alkaline Earth Metals

Groups 3-12 : Transition Metals
Lanthanide Series Actinide Series

Lithium reacting with water
Alkali Metals Group 1 The most reactive of all metals (only need to lose one electron) Have 1 electron in their outer energy levels Lithium reacting with water

Magnesium reacting with HCl
Alkaline Earth Metals Group 2 Very reactive Have 2 electrons in their outer energy levels Calcium Magnesium reacting with HCl

Transition Metals/Elements
Groups 3-12 Inner Transition Metals Lanthanide Series Atomic numbers 58-71 Named the lanthanide series because they follow Lanthanum Actinide Series Atomic numbers Named actinide series because they follow Actinium All are radioactive and unstable

The Metalloids

Metalloids 8 elements located next to the stair-step line (not Aluminum!) Have properties similar to metals and nonmetals On p.11 outline the metalloids in green.

Metalloids ME TA L L O I D S

Other Metals Other Metals

Nonmetals Poor conductors of heat and electricity
Usually gases or brittle solids at room temperature Exception: Bromine is a liquid at room temperature. On p.11, outline Bromine (Br) in blue On p.11, outline all of the GASES in red. (H, He, N, O, F, Ne, Cl, Ar, Kr, Xe, Rn) Located to the right of the stair-step line. On p.11 label the right half of the Periodic Table “Nonmetals.” Exception: Hydrogen is a nonmetal, but is located to the left of the stair-step line. Tend to accept electrons in chemical reactions with metals Tend to share electrons in chemical reactions with other nonmetals

The Nonmetals

Group 17: Halogens Halogens

Group 18: Noble Gases Noble Gases

Other Nonmetals Other Nonmetals

Halogens Group 17 The most reactive of all nonmetals (only need to gain one electron) Have 7 electrons in their outer energy levels

Noble Gases Group 18 Stable (not reactive) because outermost energy levels are full Have 8 electrons in their outer energy levels

Other Nonmetals Also referred to as the Boron group Carbon group
Nitrogen group Oxygen group On p. 11, make a key for your Periodic Table Liquids Gases Metalloids