Periodic Table Web QuestPre-AP Chemistry

Mendeleev

Dmitri Mendeleev lived and worked in Russia

He developed his model of the periodic table in the 1860s, but published it in 1869

Mendeleev arranged the elements by their atomic masses and their properties

Mendeleev’s periodic table

Mendeleev left gaps in his periodic table to allow for elements that had not been identified, even predicting their properties

Modern Periodic Table

The modern periodic table arranges the elements in rows (periods) by their atomic numbers.

Elements having the same number of valence electrons, and similar properties, are in vertical groups or families.

Alkali Metals: Group I

Characteristics- have one valence e-, form 1+ ions, low density (float ), very reactive, explode when exposed to water, softer than most metals, good conductors of heat and electricity, form salts with halogens

Examples: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr)

Alkali metals

Uses- batteries, lubricants, alloys, gunpowder, salts, paper industry, fertilizer, detergent

Alkaline Earth Metals: Group 2

Characteristics- very reactive, form 2+ ions, shiny, soft, react vigorously with oxygen

Uses- alloys, Mg is important in chlorophyll, engine parts, Ca needed for teeth and bones, blood clotting, building material, paper, food nutrients

Examples- Be, Mg, Ca, Sr, Ba, Ra

Alkaline Earth metals

Transition Metals

Characteristics- from colored compounds, good conductors of heat and electricity, malleable and ductile, high melting and boiling points (except Hg), can have several oxidation states

Uses- catalysts, corrosion resistant alloys, steel, engines, paint pigments, batteries, building materials, coins

Examples- Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn

Transition Metals

Metalloids

Characteristics- solids, semiconductors of heat and electricity, have properties of both metals and nonmetals

Uses- glass, lubricants and adhesives, alloys, transistors, electronics, batteries

Examples- B, Si, Ge, As, Sb, Te, Po

Metalloids

Chalcogens: Oxygen family

Characteristics- form 2- ions, properties vary (oxygen is a colorless gas, while sulfur is a yellow solid, etc.), “ore-formers”

Uses- oxygen needed for cellular respiration and combustion, sulfur used in gunpowder and rubber, selenium is in solar cells and dandruff shampoo, tellurium is used in paints and lubricants

Examples- O, S, Se, Te, and Po

Chalcogens—oxygen family

Halogens: fluorine family

Characteristics- very reactive, form -1 ions, form salts with metals, all phases of matter represented (gas- F, Cl; liquid-Br; solid- I, At)

Uses- nonstick coatings, glass etching, toothpaste, bleach, disinfectant, pesticides, thyroid hormones, medicines

Examples- F, Cl, Br, I, At

Halogens

Noble Gases

Characteristics- generally nonreactive due to having an octet of valence electrons, odorless gases, conduct electricity and fluoresce, nonflammable

Uses- lighting, lasers, medical imaging and anesthetic (Xe), radiotherapy, balloons

Examples- He, Ne, Ar, Kr, Xe, Rn

Nobel Gases