Presentation on theme: "Objectives: AHSGE Reading 4.3 Discern organizational patterns. Other AOD C.3.2 Recognize periodic trends of elements, including the number of valence electrons,"— Presentation transcript:
Objectives: AHSGE Reading 4.3 Discern organizational patterns. Other AOD C.3.2 Recognize periodic trends of elements, including the number of valence electrons, atomic size, and reactivity.
Periodic Law Dmitri Mendeleev’s periodic table had the elements arranged in order of increasing mass. There is a periodic repetition of chemical and physical properties of the elements when they are arranged by increasing atomic number
Modern Periodic Table What are the columns called? Answer: Groups What are the horizontal rows called? Answer: Periods Label groups & rows on your periodic table!!
Modern Periodic Table Representative elements: elements in the A groups (1A-8A) “the main group” Possess a wide range of physical and chemical properties Transition elements: elements in the B groups (1B-8B)
Metals Describe some properties of metals. Metals: Generally shiny Most are solid at room temperature Good conductors of heat and electricity Ductile and malleable Most group A and all group B elements are metals.
Groups 1A and 2A, EXCEPT HYROGEN, are metals. The other elements in group 1A are called alkali metals. Reactive & Readily combine with group 6 and 7 elements. Group 2A elements are alkaline earth metals. Contain a pair of electrons in their outermost shell.
Both groups 1A and 2A are highly reactive (1A more so). Why would group 1A be more reactive than group 2A? Answer: Group 2A has a FILLED s orbital, but group 1A’s s orbital is only half-filled, so that electron is still looking for a partner to hook up with.
Group B elements: Transition metals: located on the main body of the periodic table Inner transition metals: the 2 rows located along the bottom of the periodic table
Nonmetals Describe some properties of nonmetals. Nonmetals: Generally gases or brittle, dull-looking solids Poor conductors of heat or electricity The ONLY nonmetal that is a liquid at room temperature is bromine. Located in the upper right portion of the periodic table
Halogens: Group 7A elements; highly reactive Noble gases: Group 8A; extremely Unreactive. Why are group 8A elements unreactive? Answer: Their outer valence shell is filled, so they have no need to pair up with anyone else.
Metalloids Have properties of both metals and nonmetals. Stair-step down from boron to astatine and germanium to polonium. They separate the metals and nonmetals on the periodic table.
Assignment Label the following on your blank periodic table: Groups & periods Representative elements Transition elements Metals: alkali metals, alkaline earth metals, transition metals, and inner transition metals Nonmetals Halogens Noble gases metalloids