Chapter 10 The Periodic Table Lesson 1 Using
+ Chapter 10: The Periodic Table
+ Lesson 1: Using the Periodic Table Vocabulary words: Periodic table Group Period
+ What is the periodic table? n Scientists use the periodic table to organize the elements. n It is a chart of the elements arranged into rows and columns according to their physical and chemical properties. n It can be used to determine the relationships among the elements as well.
+ Developing a Periodic Table n 1869 - Dimitir Mendeleev was working on a way to classify the elements. n He studied their physical and chemical properties (density, color, how they react with other elements, etc) n Mendeleev ended up organizing the elements by their atomic masses and noticed the repetition of the properties. n He arranged them in rows by increasing atomic mass. n Elements with similar properties were in the same column.
+ Patterns in Properties n Melting n The point, boiling point, density physical properties are repeated in a pattern.
+ Predicting Properties of Undiscovered Elements n When Mendeleev arranged all known elements by increasing atomic mass, there were large gaps between some elements. n He predicted that some scientists would fill in those gaps with elements they discovered. n He also predicted that the properties of these elements would be similar to the known elements in that column.
+ Changes to Mendeleev’s Table n There was one problem with the table. Some elements seemed out of place. n Mendeleev believed that the atomic masses of some elements must be invalid because the elements appeared in the wrong place on the table. n He place Tellerium before Iodine because Iodine’s properties resembled those of F and Cl. n Even though Tellerium had a greater atomic mass n
+ The Importance of Atomic Number n In the 1900 s, Henry Mosley solved Mendeleev’s problem n He organized the elements by AN rather than AM. n This allowed the columns now to have elements with similar properties. n AN= number of protons in the nucleus of an atom
+ Today’s Periodic Table n The table is organized into columns, rows, and blocks, which are all based on certain property patterns. n Physical and chemical
+ Groups n. A group is a column on the periodic table. n Have similar properties and react with other elements n Patterns in physical properties of a group are density, melting point, and boiling point.
+ Periods n. A period is a row on the periodic table. n As you read from left to right, the AN increases n The physical and chemical properties also change as you move left to right.
+ Metals, Nonmetals, and Metalloids n¾ of the elements on the periodic table are metals. They are located on the left side and in the middle of the table. n All metals are shiny and conduct thermal energy and electricity. n They also have some properties that differ. n
+ Metals, Nonmetals, and Metalloids are located on the right side of the periodic table n Nonmetals n Except hydrogen n Many are gases and do not conduct thermal energy or electricity n Metalloids have properties of metals and nonmetals.
+ How Scientists Use the Periodic Table n New elements are created, named, and added to the present-day periodic table. n Elements (such as Bohrium and Hassium) are all synthetic or man-made and do not occur naturally on Earth. n They can predict the properties of new elements.
+ Lesson 2: Metals Vocabulary words: Metal, luster, ductility, malleability, alkali metal, alkaline earth metal, transition metal
+ What is a metal? n To be a metal, an element must have certain properties. n n. A Physical properties describe something without changing its makeup or identity metal is an element that it generally shiny. It is easily pulled into wires or hammered into thin sheets. A metal is a good conductor of electricity and thermal energy.
+ Luster and Conductivity n Luster n is the ability of a metal to reflect light. Gold is used for jewelry because it has great luster. n Gold is also a good conductor of thermal and electricity. n Gold is too expensive to use in wiring or cookware so Copper is used instead.
+ Ductility and malleability n Ductility n Gold is the ability to be pulled into thin wires. is the most ductile metal. is the ability of a substance to be hammered or rolled into sheets. n Malleability n Gold is very malleable.
+ Other properties n Density, strength, boiling point, and melting point of metal are greater than those of other elements. n All metals are solid at room temperature except for Hg. n Chemical properties The ability or inability of a substance to change into a new substance n Differ greatly but those is the same group have similar chemical properties n
+ Alkali Metals n The n elements in group 1 Lithium, Sodium, Potassium, Rubidium, Cesium, and Francium n React quickly with other elements They occur only in compounds n Pure alkali metals must be stored so they do not come in contact with oxygen and water vapor n
+ Alkali Metals n Physical Properties Silvery appearance n Soft n Lowest density of all metals n For example, a block of sodium can float on water n
+ Alkaline Earth Metals n Elements n n in group 2 Be, Mg, Ca, Sr, Ba, Ra React quickly with other elements (but not as quickly as alkali metals) n Pure n metals do not occur naturally They combine with other elements and form compounds
+ Alkaline Earth Metals n Physical properties Soft n Silvery n Low density but it is greater than alkali metals n
+ Transition Elements n The n elements in group 3 -12 Includes the center of the periodic table and the two rows on the bottom n Properties Higher melting points, densities, and strength than AM and AEM n Do not react as fast with oxygen n Some can exist as free elements (when it occurs in pure form, not in a compound) n
+ Uses of Transition Elements n Make n Resistance to corrosion n Make n good building materials (Fe) coins (Cu, Ag, Ni, Au) Jewelry, wires, and industrial applications n Artists use transition-element compounds in paints and pigments n Some gems, garnets and emeralds, come from the presence of small amounts of transition elements.
+ Lanthanide and Actinide Series n These elements are removed from the main part of the table so periods 6 & 7 are not longer than the other periods. n Lanthanide n Used to make strong magnets n Actinide n is between Lanthanum and Halfnium is between Actinium and Rutherfordium Plutonium is used fuel for nuclear reactors
+ Patterns in Properties of Metals n Elements increase in metallic properties as you read from right to left across a period n Elements on far right have no metallic properties n Potassium has the highest luster, is the most malleable, and conducts electricity better than all the elements in this period.
+ Patterns within Groups n Metallic properties tend to increase as you move down a group n Whose malleability is greater? Gold, Silver, Copper?
+ Lesson 3: Nonmetals & Metalloids Vocabulary words: Nonmetal, halogen, noble gas, metalloid, semiconductor
+ The Elements of Life n The mass of your body comes from four nonmetalsoxygen, carbon, hydrogen, and nitrogen n Nonmetals are elements that have no metallic properties. n Of the remaining elements, the two most common are sulfur and phosphorus. n These six elements form compounds in proteins, fats, nucleic acids, and large molecules.
+ How are nonmetals different from metals? n Nonmetals n Those n Poor n are gases at room temperature that are solid have no luster conductors Good insulators
+ Nonmetals in groups 14 -16 n These groups contain metals, nonmetals, and metalloids n The chemical properties are similar but the physical properties can be different n Group 14: Carbon Family Carbon is the only nonmetal n It is in most of compounds that make up living things n
+ Group 14 -16 n Group 15: Pnictogen Nitrogen (gas) and Phosphorus (solid) are the only nonmetals n These form many different compounds especially with oxygen n n Group n 16: Chalcogen Three nonmetals: Oxygen (gas), Sulfur (solid), and Selenium (solid) n Oxygen is essential to organisms
+ Group 17: Halogens n. A n halogen is an element is group 17 Flourine, Chlorine, Bromine, Iodine n Halogen means an element that can react with a metal and form a salt Chlorine reacts with sodium= table salt n Calcium chloride= salt for icy roads n
+ Halogens n React with other elements and form compounds Therefore, they act only in compounds naturally n They do not exist as free elements n Usually react with other nonmetals like Carbon n They are less reactive as you move down the group n
+ Group 18: Noble Gases n Noble n gases are elements in group 18 Helium, Neon, Argon, Krypton, Xenon, and Radon n Do not react with other elements unless in a laboratory n These were not discovered when Mendeleev made the periodic table because they did not form compounds naturally n Once they were discovered, a group was added on the far right
+ Hydrogen n Has the smallest atomic mass n Most common element in the universe n Is classified as a nonmetal because on Earth it behaves like nonmetal n n Gas at room temperature However, it also has similar properties to Alkali Metals n Conducts electricity in its liquid state n Reacts with other elements
+ Metalloids n. A metalloid is an element that has physical properties of a metal and nonmetal. n B, Si, Ge, As, Sb, Te, Po, At n Silicon is the most abundant metalloid in the universe. Most sand is made up of a compound containing Silicon. n Used in glass n Electronic devices n Medical tubing n
+ Semiconductors n. A property of a metalloid is to act as a semiconductor. n. A semiconductor conducts electricity at high temperatures, but not at low temperatures. At high temp- metalloids act as metals and conduct electricity n At low temp- they act like nonmetals and do not allow electricity to flow easily n
+ Properties and Uses of Metalloids n Silicon: compounds create sand, clay, rock, minerals, & pure silicon are semiconductors for computers and other electronic products n Germanium: n Boron: semiconductors water softeners, and laundry products. It also glows green in fireworks
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