section 1-3 objectives - new rockford-sheyenne school 1-3 objectives 1) ... stainless steel...
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Section 1-3 Objectives
1) Identify some of the more important metals from the
alkali and alkaline earth groups.
2) Describe the differences in characteristics between the
metals of the alkali and the alkaline earth groups.
3) Locate the transitional metals on the periodic table.
4) Name some of the important transitional metals and
describe some of their uses.
5) Define the term alloy and name several important alloys
of transition metals.
6) Locate the inner transition metals on the periodic table.
7) Describe the general properties of the lanthanide and
actinide series of elements.
• The most reactive metals.
• s-block elements is located of the 1A and 2A groups.
• Alkali metals and alkaline earth metals.
• Most abundant elements include:
• Alkali metals: sodium (Na) and potassium (K)
• Alkaline earth metals: calcium (Ca) and magnesium
(Mg)
6-1 Reactive Metals: The s-block Elements
Alkali Metals
• Properties:
• Shiny solids that are malleable, ductile, and good
conductors of electricity.
• Low density and low melting points.
• Very soft and can be cut with a knife.
• Very reactive and tarnish rapidly with exposure to
oxygen in the air.
• Single valence electron causes reactivity with
moisture which increases down the group.
Alkali Metals: Sources and Uses
• All alkali metals react with halogens (7A): ex. NaCl
• Alkali metals = 1 valence electron
• Halogens = 7 valence electrons
• Create a full outer electron shell
• Sources:
• Alkali metals are never found in an elemental state in
nature because they are very reactive.
• Compounds made with alkali metals are very soluble
in water
• Common compounds: table salt (NaCl), Lye (NaOH),
bleach (NaClO), baking soda (NaHCO3)
Alkaline Earth Metals: Properties
• Group 2A = 2 valence electrons
• React strongly with group 6A Oxygen group
• Also react with halogens to form compounds (MgCl2)
• Not quite as reactive as the alkali metals but are still
considered reactive.
• Higher densities and melting points than alkali metals.
• Alkaline earth metals will form ions with a 2+ charge
Alkaline Earth Metals: Sources and Uses
• Because of reactivity, they are not found in an elemental
state in nature.
• They can be found in compounds such as limestone
(CaCO3) and magnesite (MgCO3)
• Alloy: when one metal is added to another metal.
• Alloys of magnesium and aluminum is an important
structural metal.
• Used to make aircraft, tools and car rims.
• Light and strong
• Beryllium is slightly different: strong and high melting
point – component of emeralds.
• These elements are located in the middle of the periodic
table.
• Composed of groups 1B- 8B
• Transition metal properties:
• High densities and high melting points
• Strong and structurally useful
• Other properties vary across the periodic table
• Important transitional metals include Chromium, Iron,
Copper, Silver and Gold
6-2 Transition Metals: the d-block Elements
Chromium
• Source: found in deposits located in
Russia, the Phillipines, and southern
Africa.
• Properties: hard, silvery metal that is
very resistant to corrosion (reaction
with water, oxygen or acids)
• Uses:
• Forms many useful alloys: ex.
Stainless steel
• Compounds with chromium exhibit a
wide range of colors: ex.
Gemstones, paint pigments
Iron
• Source:
• 4th most abundant element found in the Earth’s crust.
• Usually found as rust (Fe2O3) because of its reactivity
to oxygen
• Properties: Produces alloys that are strong, durable and
resistant to corrosion.
• Uses:
• Forms compounds that are red in color
• Iron attaches to hemoglobin and carries oxygen
throughout the body.
Coinage Metals: Gold, Silver and Copper
• Sources:
• Found in compounds and elemental states in nature.
• Properties: resistant to corrosion, shiny and malleable
• Uses: Used throughout history to make coins, wires and
strong alloys (bronze) to make weapons
Copper, Silver and Gold
• Copper: soft metal used to make bronze.
• Slightly resistant to corrosion but will react with
oxygen and CO2 to create a patina (greenish coating).
• Silver: lustrous, white metal that is very ductile and
malleable.
• Used in coinage, jewelry, silverware and wiring.
• Silver will react with sulfide ions to create a tarnish.
• Gold: dense, soft, yellow metal.
• Usually found in an alloy because it is so soft.
• Used in jewelry and coinage.
• Composed of the Lanthanides and Actinides.
• Located at the bottom of the periodic table, detached
from the other groups.
• These elements belong between the s- and d- block
elements.
• Electron configurations of f-block elements are
complicated and do not follow a regular pattern.
6-3 Inner Transition Metals: the f-block
Elements
Lanthanides
• Source: Widely distributed in nature but are found
together because their properties are so similar.
• Properties:
• Form 3+ ions
• Soft, silvery metals
• Too reactive to be used in structural materials.
• Uses: making special steel alloys and compounds that
create the color in televisions