Chapter 5 Metals Vs. Nonmetals
Metals Metals are elements found to the left of the stair step line. Metals are good conductors of heat and electricity. Metals are solid at room temperature except Mercury (Hg) Metals reflect light which is a property called luster. Metals are malleable, which means they can be hammered or rolled into thin sheets. Metals are ductile, which means they can be drawn into wires.
Properties of Metals Metals-Physical Metals- Chemical Good conductors of heat and electricity Easily lose electrons (form cations (+) ions) Luster (shininess) Corrodes easily High density Reactive High melting point Examples of Cations Ductile and Malleable Na+ , Mg2+, Al3+ Solid at STP (except Hg)
Alkali Metals Group 1 on the periodic table. Good conductors, shiny, malleable, and ductile Softer than most metals. Most reactive of all metals- Reacts violently with water (H2O) and oxygen (O) Readily combine with other elements and don’t occur in nature by themselves. Each atom has 1 ve- in its outer energy level. This e- is given up when it combines with a nonmetal, thus making it a 1+ cation charge. Electron configuration ends in Xs1
Alkaline Earth Metals Make up group 2 of the periodic table Shiny, malleable, and ductile Not found as free elements in nature, because they combine so readily with other elements. Each atom has 2 e- in its outer energy level. These 2ve- are given up when they combine with a nonmetal, thus making it a cation with a 2+ charge. Electron configuration ends in Xs2
All blocks contain at least one element from each period. Why are both hydrogen and cesium s-block elements, when hydrogen has one electron and cesium has 55? All blocks contain at least one element from each period. Blocks of elements on the periodic table are based only on an element's valence electrons. The s-block includes only the most reactive elements. They have identical electron configurations.
Atoms of elements in group 2 have ____________. one electron in their outermost energy level two electrons in their outermost energy level seven electrons in their outermost energy level eight electrons in their outermost energy level
Physical Properties of Nonmetals Elements that usually are gases or brittle solids at room temperature Solids- Brittle, powdery, are not malleable or ductile Do not conduct heat or electricity well No luster- Dull Found to the right side of the stair step line
Chemical Properties in Nonmetals The e- in most nonmetals are strongly attracted to the nucleus of atoms. Form ionic and covalent compounds When Nonmetals Gain e- from metals. They form ionic compounds. When 2 nonmetals share electrons with other nonmetals and they combine they form covalent bonds or molecular compounds.
Properties of Non Metals Non Metals-Physical Non Metals- Chemical No luster (dull) often colored Tends to gain electrons from metals to form ionic bonds Poor conductors of heat and electricity Share electrons with other nonmetals to form Low Density Low Boiling Point molecules or covalent compounds Non Ductile and Malleable Reactivity increases upward Brittle F is the most active
Halogens Group 17- Form Halide compounds Very reactive in their elemental form, but their compounds have many uses Gains 1e- from metals to form ionic compound F is the most chemically active of all the elements Exist as diatomic molecules Electron configuration ends in Xs2Xp5
Noble Gases ALWAYS exist as ISOLATED ATOMS They are stable because their most outer energy levels is full with 8e- Helium has 2ve-, but its 1st energy level is still full They are colorless, odorless, and tasteless. They are sometimes called inert gases because they rarely take part in a chemical reaction. Electron configuration ends in Xs2Xp6
Atoms of elements in group 17 have ____________. one electron in their outermost energy level two electrons in their outermost energy level seven electrons in their outermost energy level eight electrons in their outermost energy level
Which of the following is incorrect in regards to group 18 Noble Gases? Has 8 valence electrons and has a full outer energy level. Does not bond with other elements on the periodic table. Likes to gain and receive electrons. Has an outer electron configuration of Xs2Xp6
Properties of Metalloids Have properties of both metals and nonmetals. Solids Shiny or dull Ductile Malleable Conduct better than nonmetals but not as well as metals.
Which of the following are poor conductors of heat and electricity? Metals Metalloids Nonmetals alkaline earth elements