Mercury Facts - Periodic Table of the Elements

Mercury Facts - Periodic Table of the Elements Mercury is the only metallic element that is a liquid at room temperature. This dense metal is atomic number 80 with element symbol Hg. This collection of mercury facts includes atomic data, the electron configuration, chemical and physical properties, and history of the element. Mercury Basic Facts Symbol: HgAtomic Number: 80Atomic Weight: 200.59Element Classification: Transition MetalCAS Number: 7439-97-6Mercury Periodic Table LocationGroup: 12Period: 6Block: d Mercury Electron Configuration Short Form: [Xe]4f145d106s2Long Form: 1s22s22p63s23p63d104s24p64d105s25p64f145d106s2Shell Structure: 2 8 18 32 18 2 Mercury Discovery Discovery Date: Known to the ancient Hindus and Chinese. Mercury has been found in Egyptian tombs dating to 1500 B.C.Name: Mercury derives its name from the association between the planet Mercury and its use in alchemy. The alchemical symbol for mercury was the same for the metal and the planet. The element symbol, Hg, is derived from the Latin name hydragyrum meaning water silver. Mercury Physical Data State at room temperature (300 K): LiquidAppearance: heavy silvery white metalDensity: 13.546 g/cc (20  °C)Melting Point: 234.32 K (-38.83  °C or -37.894  °F)Boiling Point: 356.62 K (356.62  °C or 629.77  °F)Critical Point: 1750 K at 172 MPaHeat of Fusion: 2.29 kJ/molHeat of Vaporization: 59.11 kJ/molMolar Heat Capacity: 27.983 J/mol ·KSpecific Heat: 0.138 J/g ·K (at 20  °C) Mercury Atomic Data Oxidation States: 2 , 1Electronegativity: 2.00Electron Affinity: not stableAtomic Radius: 1.32 Ã…Atomic Volume: 14.8 cc/molIonic Radius: 1.10 Ã… (2e) 1.27 Ã… (1e)Covalent Radius: 1.32 Ã…Van der Waals Radius: 1.55 Ã…First Ionization Energy: 1007.065 kJ/molSecond Ionization Energy: 1809.755 kJ/molThird Ionization Energy: 3299.796 kJ/mol Mercury Nuclear Data Number of isotopes: There are 7 naturally occurring isotopes of mercury..Isotopes and % abundance: 196Hg (0.15), 198Hg (9.97), 199Hg (198.968), 200Hg (23.1), 201Hg (13.18), 202Hg (29.86) and 204Hg (6.87) Mercury Crystal Data Lattice Structure: RhombohedralLattice Constant: 2.990 Ã…Debye Temperature: 100.00 K Mercury Uses Mercury is amalgamated with gold to facilitate the recovery of gold from its ores. Mercury is used to make thermometers, diffusion pumps, barometers, mercury vapor lamps, mercury switches, pesticides, batteries, dental preparations, antifouling paints, pigments, and catalysts. Many of the salts and organic mercury compounds are important. Miscellaneous Mercury Facts Mercury compounds with the 2 oxidation states are known as mercuric in older texts. Example: HgCl2 was known as mercuric chloride.Mercury compounds with the 1 oxidation state are known as mercurous in older texts. Example: Hg2Cl2 was known as mercurous chloride.Mercury is rarely found free in nature. Mercury is harvested from cinnabar (mercury(I) sulfide - HgS). It is extracted by heating the ore and collecting the mercury vapor produced.Mercury is also known by the name quicksilver.Mercury is one of the few elements that is liquid at ordinary room temperatures.Mercury and its compounds are highly poisonous. Mercury is readily absorbed across unbroken skin or though the respiratory or gatroinstestinal tract. It acts as a cumulative poison.Mercury is very volatile in air. When room temperature air (20 °C) is saturated with mercury vapor, the concentration greatly exceeds the toxic limit. The concentration, and thus the danger, increases at higher temperatures.Early alchemists believ ed all metals contained varying amounts of mercury. Mercury was used in many experiments to transmute one metal into another. Chinese alchemists believed mercury promoted health and extended life and included it with several medicines.Mercury readily forms alloys with other metals, called amalgams. The term amalgam literally means alloy of mercury in Latin.An electrical discharge will cause mercury to combine with the noble gases argon, krypton, neon, and xenon.Mercury is one of the heavy metals. Many metals have a higher density than mercury, yet are not considered to be heavy metals. This is because heavy metals are both extremely dense and highly toxic. Sources Eisler, R. (2006). Mercury hazards to living organisms. CRC Press. ISBN 978-0-8493-9212-2.Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0-08-037941-9.Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.Norrby, L.J. (1991). Why is mercury liquid? Or, why do relativistic effects not get into chemistry textbooks?. Journal of Chemical Education. 68 (2): 110. doi:10.1021/ed068p110Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4. Return to the Periodic Table

Hypermiling (Saving Lots of Fuel) in a Hybrid

Hypermiling (Saving Lots of Fuel) in a Hybrid Hypermiling is an endless pursuitthe quest for improved fuel economy, ratcheted up a couple of notches to near fanaticism. Those who practice it are called hypermilers, a dedicated group of guys and gals who routinely push the limits of maximum fuel efficiency. It got its name from the likes of Wayne Gerdes, one of the original devotees of hypermiling, and often proclaimed the inventor of the term. Hypermiling more or less got its start with hybrids, but its not limited to them. Here, well focus on hypermiling with a hybrid vehicle. Some of the techniques can only be done with a hybrid, or, at least they make it much easier and saferthough some hardcore hypermilers perform ALL of these techniques in regular cars. We dont recommend that, but really, a lot of it is just plain common sense that can be applied to just about any vehicle and/or driver. So what are these techniques and tools that are employed so passionately by their devotees? Read on for an explanation of these FE (thats hypermileresque for Fuel Economy) tricks. Pulse and Glide (PG) This is the heart of effective hypermiling for full hybrid vehicles. Though it takes some getting used to, and its really only appropriate for light suburban and town traffic, large FE gains can be had using it. Our first successful PG was in a Nissan Altima Hybrid. This car is equipped with Toyotas Hybrid Synergy Drive (Nissan licensed it from Toyota), but our car was lacking an energy flow monitor, so we had to rely on the EV mode display and the Kilowatt (kW) meter to execute the task properly. To initiate a PG, accelerate to about 40 MPH with the engine running (the pulse part), then ease off the pedal until the hybrid system goes into EV (electric vehicle) mode and the kW meter shows zero (or if equipped with the energy flow monitor, no arrows are showing energy flow). This is the glide part. The engine is off, the electric motor is disengaged and the vehicle is literally coasting for free. When the car slows to about twenty-five or thirty MPH (depending on traffic conditions, of course) repeat the pulse part, then the glide and so on. If properly applied, this trick uses the engine only to accelerate, and it never has the chance to idle along, wasting fuel while providing no return. Forced Auto Stop (FAS) Forced Auto Stop is similar to PG without the objective of re-accelerating. In a hybrid, it is usually a matter of lifting the accelerator below a speed of approximately 40 MPH and letting the engine shut-off. This allows the car to coast to a slower speed, or come to a complete stop without the engine running. However, many conditions can affect FAS (adequate battery state of charge, hybrid system temperature, engagement of AC compressor, cabin heat, etc.) and are not always so simple. Depending upon the hardware and software controls of the hybrid system, there are ways to fool the system into FAS. Unfortunately, they are many and varied, and beyond the scope of this article. Draft Assisted Forced Auto Stop (D-FAS) This technique involves riding in the wake of a large trailer truck at highway speeds (in FAS). Its not safe, DONT DO IT. We only mention it here because it is part of some hypermilers arsenal of tricks. Driving Without Brakes (DWB) More hypermilers tongue-in-cheek terminology. We like to think of this as driving with minimal brakes, but it must be done with a good dose of common senseits really not a good idea to take a 25 MPH curve at 50 trying to save gas. The main idea here is to not use the brakes to scrub off speed that has been achieved with energy (gasoline) spent. Anticipation is the keyword. Look far down the road to anticipate traffic stoppages, sharp curves, and signal changes and begin to decelerate or coast beforehand. The benefit is three-fold: Not only does DWB increase brake life, it reduces the number of times the vehicle must be started from a dead-stop (overcoming the inertia of a stationary vehicle consumes an enormous amount of energy), and, with a hybrid, the coasting action (regenerative braking) helps charge the battery. Ridge Riding This is the practice of driving very close to the outside edge of the road in order to keep the vehicles tires out of the slight depressions (ruts) worn into the road surface by the constant pounding of daily traffic. For most purposes, this technique is really only effective on wet roadways. Staying out of the ruts, which are filled with a thin layer of water, reduces drag on the tires and increases efficiency. An additional benefit is improved safety by preventing the tires from hydroplaning (riding on top of the water) and loss of vehicle control. Face out Potential Parking This is just plain common sense with a little bit of exercise, to boot. Search out open spaces in parking lots to eliminate the wasteful movement of backing out of a slot. Go one better by locating a spot that is on a bit of a slope, and then use gravity to help get the vehicle moving from a standstill. Sound silly? Multiply those effects over hundreds of park jobs in a year; it really does add up. Fuel Consumption Display (FCD) This is the gauge on the instrument panel of hybrids and many non-hybrids as well. Dedicated hypermilers call this the game gauge, and in many ways, thats just what it is. This device continuously calculates a vehicles average fuel consumption expressed in MPG (or, in metric mode, kilometers/liter) and displays it to the driver who can then make a fantastic game of making the average FE go ever upwards. Instant Fuel Consumption Display (IFCD) The instant fuel consumption display is very similar to the FCD, except that it displays fuel usage, just as the name impliesinstantlyas it is used. The display changes moment by moment in response to sundry dynamic physical conditions: throttle off, light acceleration, heavy load, hard acceleration, coasting and cruising. This gauge, more than any other on a vehicle, hammers home the relationship between fuel economy and driving habits. Keeping the instant fuel consumption display relatively constant and even, with a high reading, will probably net more consistent (and easily attainable) FE than any trick or gadget outlined in this entire article.