Chemistry 5C

Nichrome (nickel-chrome)

• Refers to any alloy of nickel, chromium, and often iron and/or other elements or substances.
• Nichrome alloys are typically used in resistance wire.
• Also in dental restorations (fillings).
• Has a high electrical resistance, and will heat up without degrading itself.

Galvanization

• The process of applying a protective zinc coating to steel or iron, to prevent rusting.
• Most common method is hot-dip galvanization. (parts are submerged into molten zinc).
• Protects in 2 ways. #1 forms a coating of corrosion-resistant zinc which prevents corrosive substances from reaching the more delicate part of the metal.
• #2 The zinc serves as a sacrificial anode so that even if the coating is scratched, the exposed steel will still be protected by the remaining zinc.

Gold

• Relatively inactive metal.

Inner Transition Metals

• Fill the f-block
• Lanthanide and Actinide Series
• Lanthanide Series-- largely paramagnetic
• Property of materials that are weakly attracted by a magnetic field because of unpaired electrons.
• Actinide series-- dangerous radioactive.

Uranium

• Energy source for generating electricity in nuclear plants.

Zinc

• German word "Zink"
• Protect exposed iron from corrosion.

Group 13: The Boron Family

• Boron, Aluminum, Gallium, Indium, Thallium.
• Possess 3 valence electrons.
• Usually wants to rid of 3, becomes +3 cation.

Boron

• Arabic word "Buraq" and the Persian word "Burah" which are both words for the material "borax."
• Used in pyrotechnics and flares to produce a green color.
• Good absorber of nuetrons and is used in the control rods of nuclear reactors, as a radition sheild and as a nuetron detector.
• Dopes silicon for transitors.

Post-Transition Metals

• Aluminum, Tin, Lead, Gallium, Indium, Thallium, and Bismuth.
• Bismuth compound in Pepto-Bismol corrects most digestive problems.

Aluminum

• Forms corrosion proof reflecting coating for telescope mirrors.

Group 14: The Carbon Family

• Carbon, Silicon, Germanium, Tin, Lead
• Possesses 4 valence electrons
• Either share or give away 2 valence electrons
• Carbon exists in all allotropes.
• They use lead in car battery lead plates, lead glass, and lead bullets.

Metalloids

• Semiconductors-- will allow limited movement of electrons through its structure.
• Used largely in computer industries.

Group 15: The Nitrogen Family

• Nonmetals are good insulators.
• Nitrogen, phosphorous, Arsenic, Antimony, Bismuth
• Posses 5 valence electrons, wants to gain 3 to become -3 cation or will share its own electrons

Nitrogen

• Most abundant in the earth's atmosphere by volume
• Phosphorus glow

Group 16: Chalcogens, The Oxygen Family

• Oxygen, Sulfur, Selenium, Tellurium, Polonium
• Possesses 6 valence electrons; wants to gain 2 electrons to become -2 cation
• Will also share
• Oxygen is the most abundant in earths crust by mass

Oxides and Sulfides

• Oxides are any element combined with oxygen.
• Sulfides are any element combined with sulfur.
• Sulfur is called "brimstone" in the Bible.

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