Chapter 4 Section 3 – pg 138 Metals

Metals Elements that are good conductors of electric current and heat Pg 138 Metals Elements that are good conductors of electric current and heat Tend to be shiny and bendable Majority of elements in the periodic table are metals

Physical Properties Pg 138 The physical properties of metals include luster, malleability, ductility, and conductivity Malleable: can be hammered or rolled into flat sheets or other shapes Ductile: can be pulled out, or drawn, into a long wire

Pg 139 Thermal conductivity: the ability of an object to transfer heat Electrical Conductivity: the ability of an object to transfer electric current Magnetism: attracted to magnets and can be turned into magnets

Chemical Properties Pg 139 Reactivity: the ease and speed with which a substance reacts with other substances Metals usually react by losing electrons to other atoms Sodium reacts strongly with water and air Iron reacts slowly with oxygen to form rust Corrosion: the gradual wearing away of a metal due to a chemical reaction Lithium reacting to water Iron reacts with oxygen

Metals in the Periodic Table Pg 140 Metals in the Periodic Table The reactivity of metals tends to decrease as you move from left to right across the periodic table

Alkali Metals The metals in Group 1 (Lithium down to Francium) Pg 140 Alkali Metals The metals in Group 1 (Lithium down to Francium) React with other elements by losing one electron So highly reactive that they are rarely found uncombined in nature, normally found in a compound Lithium Batteries Sodium Chloride Potassium Nitrate

Alkaline Earth Metals Group 2 Pg 141 Alkaline Earth Metals Group 2 All are fairly hard, gray-white and a good conductor of electricity Less reactive then elements in Group 1 but still highly reactive – rarely found uncombined Calcium Carbonate

Transition Metals Pg 142 Groups 3 – 12 Includes most familiar metals (iron, silver, nickel, copper, gold) Most are hard and shiny All are good conductors of electrical currents Many form colorful compounds Less reactive than Group 1 and 2 Most are found as compounds Pg 142

Metals in Mixed Groups Pg 142 Only some of the elements in Groups 13 – 15 are metals These are never found uncombined in nature Includes Tin, Lead and Aluminum In Light Blue

Lanthanides Top row of the removed rows Pg 142 Lanthanides Top row of the removed rows Sometimes mixed with more common metals to make alloys Alloy: mixture of a metal with at least one other element (usually a metal) Copper + Zinc = Brass Tin + Aluminum + Copper = Bronze Copper + Gold = Rose Gold Iron + Carbon = Steel Copper + Silver = Sterling Silver

Actinides Row below lanthanides Pg 144 Actinides Row below lanthanides Only actinium, thorium, protactinium, and uranium occur naturally on earth Others were created artificially in the lab (highly unstable)

Pg 144 Synthetic Elements Elements with atomic numbers higher than 92 are sometimes called synthetic elements Not found naturally on earth: are made Scientists make synthetic elements by forcing nuclear particles to crash into one another Particle Accelerators: move atomic nuclei faster and faster until they have reached very high speeds (used to smash nuclei together)

Chapter 4 Section 3 Homework - pg 145

1A. Explain what the terms ductility and thermal conductivity mean.

1B. Give an example of how the ductility of metal can be useful

1C. What property of metals led to the use of plastic or wood handles on many metal cooking utensils? Explain.

2A. What family of elements in the periodic table contains the most reactive metals?

2B. What area of the periodic table is the best place to look for a metal that could be used to coat another metal to protect it from corrosion?

2C. Period 4 of the periodic table contains the elements potassium, calcium, and copper. Which is the least reactive?

3A. Describe the general process by which elements are synthesized

3B. How is plutonium made?