1 W ARM UP 12/14/15 Question: What would you call NO? N 2 O 4 ? MgCl 2 ? Answer: NO = Nitrogen Monoxide N 2 O 4 = Dinitrogen Tetroxide MgCl 2 = Magnesium Chloride Goal: I will learn how to name polyatomic compounds.

2 Q UICK R ECAP Valence Electrons Outermost, involved in bonding, octet Each group shares the same # and hence similar chemical properties Oxidation number Charge after getting octet. Elements in same group have same oxidation #. Ionic Bonding Metals lose electrons (+ ions), non-metals gain electrons (- ions): opposites attract. Metal gets pronounced normal, non-metal gets “-ide” ending. Covalent Bonding Two or more non-metals can share electrons Naming involves prefixes to indicate how many of each atom.

3 ELEMENT OF THE DAY 41 – Niobium – Nb Rocket nozzles are made from niobium because the resist corrosion even at high temperatures. Commonly used in body piercing and other jewelry as it is very resistant to corrosion. Coils of niobium-titanium superconducting wire are used inside MRI machines.

4 Astronomy 1.It is commonly claimed that the Great Wall of China is the only human-made object visible from the Moon. This is false. None of the Apollo astronauts reported seeing any specific human-made object from the Moon, and even Earth-orbiting astronauts can barely see it. City lights, however, are easily visible on the night side of Earth from orbit. [121] Shuttle astronaut Jay Apt has been quoted as saying that "the Great Wall is almost invisible from only 180 miles (290 km) up." [122] (See Man-made structures visible from space.) ISScommander Chris Hadfield attempted to find it from space, but said that it was "hard as it's narrow and dun-colored." [123]Great Wall of ChinaApollo [121]Jay Apt [122]Man-made structures visible from spaceISSChris Hadfield [123] 2.Black holes, contrary to their common image, have the same gravitational effects as any other equal mass in their place. They will draw objects nearby towards them, just as any other planetary body does, except at very close distances. [124] If, for example, the Sun were replaced by a black hole of equal mass, the orbits of the planets would be essentially unaffected. A black hole can act like a "cosmic vacuum cleaner" and pull a substantial inflow of matter, but only if the star it forms from is already having a similar effect on surrounding matter. [125]Black holes [124] [125] 3.Seasons are not caused by the Earth being closer to the Sun in the summer than in the winter. In fact, the Earth is farthest from the Sun when it is summer in the Northern Hemisphere. Seasons are caused by Earth's 23.4-degree axial tilt. As the Earth orbits the Sun, different parts of the world receive different amounts of direct sunlight. When an area of the Earth's surface is oriented perpendicular to the incoming sunlight, it receives more radiation than when it is oriented at an oblique angle. In July, the Northern Hemisphere is tilted towards the Sun resulting in longer days and more direct sunlight; in January, it is tilted away. The seasons are reversed in the Southern Hemisphere, which is tilted towards the Sun in January and away from the Sun in July. [126][127]EarthSunNorthern Hemisphereaxial tiltEarth orbits the SunSouthern Hemisphere [126][127]

5 A GENDA - Bellwork / New & Good - Review HW - Notes – naming Polyatomic - Practice/HW - Homework -Ch 16 quiz TOMORROW -pg 21-27 -Ch 16 packet due

6 P ER 4, 6 TO DO LIST : Missing HW: 3, 10, 14, 21, bell work Homework tonight: pg 29 / Pg 20 (see Mr. C for which ones to skip)