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1、Properties of s-block ElementsRepresentative Elements Includes groups 1A-8A that display a wide range of physical and chemical properties Metals lose e- while Nonmetals gain e- Diagonal Relationships: some elements have similar properties to those on that neighbor them on a diagonal Ex: Lithium and
2、Magnesium have similar propertiesHydrogenHydrogen is placed in 1A only because it has one valence electron.It has properties of both metals and nonmetalsDiscovered by Henry Cavendish in 1766 and it was called flammable air.Hydrogen can be produced in a lab when a metal reacts with an acid, or when e
3、lectricity is used to separate water.Industrial hydrogen is created when water reacts with methaneGroup 1A: Alkali MetalsThe term alkali comes from the Arabic word al-quili which means ashes of the saltwater plant.Lose one electron easily to become an ion with a +1 chargeSoft enough to be cut w/a kn
4、ife, like butter.Highly reactiveGood conductors of heat and electricityAlkali metals (contd)Litihium Found in water, soil, and rocks The least reactive, does not dissolve in H2O Used in batteries for electric cars, airplane parts antibacterial agent. Sulfuric acid used in fertilizers Deep in ocean,
5、food chain begins with Hydrogen sulfide. (smells like rotten eggs)Bacteria use it as an energy sourceGroup 7AChlorine A deadly gas that can also save lives. Chlorine disinfects sewage Dentists use as pain killers HCL helps you to digest food PVC makes everyday plastics (tiles, pipes)Bromine/Iodine S
6、ilver Br & I used to coat photographic film Iodine maintains a healthy thyroid gland Iodine kills bacteria, may use tablets to disinfect waterGroup 8A: Noble GasesProperties Colorless & unreactive (not many compoundsHelium Lightest gas that escapes gravity Used in blimps, airships, balloons Also mix
7、ed with oxygen for diversNeon Neon lights emit orange light when electrons are in a lower energy state.Ar and KR Ar makes up 1% of earths atmosphere. Both are used to prolong life of filaments in light bulbs. Properties of d-Block and F-block ElementsLanthanide Vs. actinide seriesTransition metals s
8、hare properties such as conductivity, luster and malleabilityThey are hard solids with high melting & boiling points. The more unpaired electrons in the d sublevel, the greater the property Ex: Chromium is the hardest with the highest melting point.Little variation seen in atomic size, electronegati
9、vity, and IEPhysical properties are determined by their e- configurationFormation of IonsForm 2+ or 3+ (and above) ionsMost have a color due to partially filled d- orbitals. The Electrons absorb light to emit color. All except white compounds Sc, Zn, and Ti (empty or filled) They can change from one
10、 color to next if lose a chargeMagnetism & MetalsDef: The ability of a substance to be affected by a magnetic fieldFerromagnetism is the strong attraction of a substance to a magnetic field. Ions align themselves in the direction of the field Metallurgy- The branch of applied science that studies an
11、d designs methods for extracting metals from ores.Cu, Ag, Pt, and Pa are the only metals unreactive enough to be found in nature uncombined. All others are oxides or sulfides.See Figure 7-25 and 7-26 Uses for Transition MetalsCopper-electrical wiringIron-make steelAlloys- jet engines, surgical instr
12、umentsC, Na, K, Ca, Mg, and Cl are used by the human body Ex: An iron ion is in the center of each hemoglobin molecule. Hemoglobin picks up oxgyen and carries it through body.Table 7-1 shows vitamin supplementsInner Transition MetalLanthanide Series Silvery metals with high melting points. Found mixed in nature and are hard to separate Used in TV screens, movie projectors, lasers, and tinted sunglassesActinide Series Radioactive elements Only 3 exist in nature. The rest are synthetic (transuranium 92) Home smoke detectors use americium
