Instruct: Given a question, retrieve passages that can help answer the question.
Query: What's the temperature water boils at?
The boiling point of water is typically considered to be 100 °C or 212 °F. Pressure and a change in the composition of the liquid may alter the boiling point of the liquid. For this reason, high elevation cooking generally takes longer since boiling point is a function of atmospheric pressure. In Denver, Colorado, USA, which is at an elevation of about one mile, water boils at approximately 95 °C or 203 °F. Depending on the type of food and the elevation, the boiling water may not be hot enough to cook the food properly. Similarly, increasing the pressure as in a pressure cooker raises the temperature of the contents above the open air boiling point.
Group C
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum ( < Greek "" "water" and "" "silver"). A heavy, silvery d-block element, mercury is the only metal that is liquid at standard conditions for temperature and pressure; the only other element that is liquid under these conditions is bromine, though metals such as caesium, francium, gallium, and rubidium melt just above room temperature. With a freezing point of −38.83 °C and boiling point of 356.73 °C, mercury has one of the narrowest ranges of its liquid state of any metal.
The boiling points of the carbon group tend to get lower with the heavier elements. Carbon, the lightest carbon group element, sublimates at 3825 °C. Silicon's boiling point is 3265 °C, germanium's is 2833 °C, tin's is 2602 °C, and lead's is 1749 °C. The melting points of the carbon group elements have roughly the same trend as their boiling points. Silicon melts at 1414 °C, germanium melts at 939 °C, tin melts at 232 °C, and lead melts at 328 °C.
North of this area, on the slope of Mt Haszard, is Inferno Crater, filled with a striking pale blue lake of highly acidic water with a pH as low as 2.2. The crater was blasted into the side of the mountain as part of the 1886 Mount Tarawera eruption event and remains the site of the largest geyser-like feature in the world. Although the actual geyser plays at the bottom of the lake and cannot be seen, a handful of active fumaroles are visible on the shore and the cliff face behind the lake. The water level of this up-to- lake follows a complicated rhythmic cycle that is interconnected with the nearby Frying Pan Lake.
There are two conventions regarding the "standard boiling point of water": The "normal boiling point" is at a pressure of 1 atm (i.e., 101.325 kPa). The IUPAC recommended "standard boiling point of water" at a standard pressure of 100 kPa (1 bar) is . For comparison, on top of Mount Everest, at elevation, the pressure is about and the boiling point of water is .
The Celsius temperature scale was defined until 1954 by two points: 0 °C being defined by the water freezing point and 100 °C being defined by the water boiling point at standard atmospheric pressure.
The extremely high temperatures of lava flows (1200 °C; 2200 °F) cause sea water to decompose into hydrogen and oxygen. The hydrogen combines with chloride ions dissolved in sea water, forming hydrogen chloride gas (hydrochloric acid). The rapidly rising plume of gas also carries with it fine particles of volcanic glass. The hydrochloric acid and other contaminants can precipitate out rapidly and the plume may become relatively safe a few hundred meters away, however, laze plumes should be shown a degree of respect as they can and have killed people who come in contact with them. The USGS has reported that, in 2000, two people were killed by exposure to laze clouds.
Mercury is a chemical element with symbol Hg and atomic number 80. It is commonly known as quicksilver and was formerly named hydrargyrum ( ). A heavy, silvery d-block element, mercury is the only metallic element that is liquid at standard conditions for temperature and pressure; the only other element that is liquid under these conditions is bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature.
The chemical element with the highest melting point is tungsten, at ; this property makes tungsten excellent for use as filaments in light bulbs. The often-cited carbon does not melt at ambient pressure but sublimes at about ; a liquid phase only exists above pressures of and estimated (see ). Tantalum hafnium carbide (TaHfC) is a refractory compound with a very high melting point of 4215 K (3942 °C, 7128 °F). At the other end of the scale, helium does not freeze at all at normal pressure even at temperatures arbitrarily close to absolute zero; a pressure of more than twenty times normal atmospheric pressure is necessary.
A human being can survive an average of three to five days without the intake of water. The issues presented by the need for water dictate that unnecessary water loss by perspiration be avoided in survival situations. The need for water increases with exercise.
Hosts
Silicon crystallises in a giant covalent structure at standard conditions, specifically in a [[diamond cubic]] lattice. It thus has a high melting point of 1414 °C, as a lot of energy is required to break the strong covalent bonds and melt the solid. It is not known to have any allotropes at standard pressure, but several other crystal structures are known at higher pressures. The general trend is one of increasing [[coordination number]] with pressure, culminating in a [[hexagonal close-packed]] allotrope at about 40 [[gigapascal]]s known as Si–VII (the standard modification being Si–I). Silicon boils at 3265 °C: this, while high, is still lower than the temperature at which its lighter congener [[carbon]] sublimes (3642 °C) and silicon similarly has a lower [[heat of vaporisation]] than carbon, consistent with the fact that the Si–Si bond is weaker than the C–C bond.
Silicon is a crystalline solid with a blue-grey metallic lustre. Like boron, it is less dense (at 2.33 g/cm) than aluminium, and is hard and brittle. It is a relatively unreactive element. According to Rochow, the massive crystalline form (especially if pure) is "remarkably inert to all acids, including hydrofluoric". Less pure silicon, and the powdered form, are variously susceptible to attack by strong or heated acids, as well as by steam and fluorine. Silicon dissolves in hot aqueous alkalis with the evolution of hydrogen, as do metals such as beryllium, aluminium, zinc, gallium or indium. It melts at 1414 °C. Silicon is a semiconductor with an electrical conductivity of 10 S•cm and a band gap of about 1.11 eV. When it melts, silicon becomes a reasonable metal with an electrical conductivity of 1.0–1.3 × 10 S•cm, similar to that of liquid mercury.
The normal boiling point (also called the atmospheric boiling point or the atmospheric pressure boiling point) of a liquid is the special case in which the vapor pressure of the liquid equals the defined atmospheric pressure at sea level, 1 atmosphere. At that temperature, the vapor pressure of the liquid becomes sufficient to overcome atmospheric pressure and allow bubbles of vapor to form inside the bulk of the liquid. The standard boiling point has been defined by IUPAC since 1982 as the temperature at which boiling occurs under a pressure of 1 bar.
Pasteurization is a sanitation process in which milk is heated briefly to a temperature high enough to kill pathogens, followed by rapid cooling. While different times and temperatures may be used by different processors, pasteurization is most commonly achieved with heating to 161 degrees Fahrenheit (71.7 degrees Celsius) for 15 seconds. Milk is tested following pasteurization to confirm that bacteria have been killed to an acceptable level. Pasteurization kills pathogenic bacteria which occasionally may be present in milk, including those causing tuberculosis ("Mycobacterium bovis"), listeriosis ("Listeria monocytogenes"), Q fever ("Coxiella burnetii"), brucellosis ("Brucella"), campylobacteriosis ("Campylobacter"), salmonellosis ("Salmonella"), and several other foodborne illnesses (e.g., ). Pasteurization may not kill some resistant bacteria, which can eventually cause souring and spoilage of fresh milk. UHT pasteurization (Ultra High Temperature) is a more extreme form of pasteurization heating milk to a temperature high enough to kill spoilage organisms also.
Unlike other artificial sweeteners, sucralose is heat stable up to 450 °F (232 °C), so Splenda can be used as a replacement for table sugar in cooking and baking, and there are Splenda products packaged specifically for this purpose. In product testing by "Cook's Illustrated", the major drawback to cooking with Splenda was found to be that it does not produce the browning or caramelization the way table sugar does. However, "Cook's Illustrated" also found that desserts baked with Splenda were "lacking the artificial flavors that just about every other sugar substitute brings with it".
The temperature required to forge weld is typically 50 to 90 percent of the melting temperature. Iron can be welded when it surpasses the critical temperature (the A temperature) where its allotrope changes from gamma iron (face-centered cubic) to delta iron (body-centered cubic). Since the critical temperatures are affected by alloying agents like carbon, steel welds at a lower temperature-range than iron. As the carbon content in the steel increases, the welding temperature-range decreases in a linear fashion. Iron, different steels, and even cast-iron can be welded to each other, provided that their carbon content is close enough that the welding ranges overlap. Pure iron can be welded when nearly white hot; between and . Steel with a carbon content of 2.0% can be welded when orangish-yellow, between and . Common steel, between 0.2 and 0.8% carbon, is typically welded at a bright yellow heat.
The dissolution of the different crystalline phases of calcium sulfate in water is exothermic and release heat (decrease in Enthalpy: ΔH < 0). As an immediate consequence, to proceed, the dissolution reaction needs to evacuate this heat that can be considered as a product of reaction. If the system is cooled, the dissolution equilibrium will evolve towards the right according to the Le Chatelier principle and calcium sulfate will dissolve more easily. The solubility of calcium sulfate increases thus when the temperature decreases. If the temperature of the system is raised, the reaction heat cannot dissipate and the equilibrium will regress towards the left according to Le Chatelier principle. The solubility of calcium sulfate decreases thus when temperature increases. This contra-intuitive solubility behaviour is called retrograde solubility. It is less common than for most of the salts whose dissolution reaction is endothermic (i.e., the reaction consumes heat: increase in Enthalpy: ΔH > 0) and whose solubility increases with temperature. Another calcium compound, calcium hydroxide (Ca(OH), portlandite) also exhibits a retrograde solubility for the same thermodynamic reason: because its dissolution reaction is also exothermic and releases heat. So, to dissolve higher amounts of calcium sulfate or calcium hydroxide in water, it is necessary to cool down the solution close to its freezing point instead of increasing its temperature.
Unlike electroplated nickel, electroless nickel deposits do not have a precise melting point but rather have a melting "range". Pure nickel has a melting point of 1455 °C (2650 °F), however EN is an alloy and as the phosphorus content is increased within the film, the deposit begins to soften at lower temperatures and continues to soften until it eventually melts. The melting range decreases linearly as the phosphorus levels increase. The eutectic or lowest melting point for NiP alloys is 880 °C (1620 °F) and occurs at a deposit phosphorus content of 11% b.w. The highest melting point is for low Phosphorus deposits (less than 3%) that claim to have melting points at 1,200 °C (2,200 °F). EN has failed in some high temperature applications since it was not fully recognized that even with a relatively high melting range the deposit may still have a liquid phase at lower temperatures. Figure 3 illustrates what happens when you subject EN to temperatures above its melting point.
Using the measured stellar luminosity of Gliese 581 is of 0.013 times that of our Sun, it is possible to calculate Gliese 581c's effective temperature a.k.a. black body temperature. (note: this probably differs from its surface temperature). According to Udry's team, the effective temperature for Gliese 581c, assuming an albedo (reflectivity) such as Venus' (0.64), would be , and assuming an Earth-like albedo (0.296), then it would be , a range of temperatures which overlaps with the range that water would be liquid at a pressure of 1 atmosphere. However, the effective temperature and actual surface temperature can be very different due to the greenhouse properties of the planetary atmosphere: for example, Venus has an effective temperature of , but a surface temperature of (mainly due to a 96.5% carbon dioxide atmosphere), a difference of about .
Pressure in the primary circuit is maintained by a pressurizer, a separate vessel that is connected to the primary circuit and partially filled with water which is heated to the saturation temperature (boiling point) for the desired pressure by submerged electrical heaters. To achieve a pressure of , the pressurizer temperature is maintained at 345 °C (653 °F), which gives a subcooling margin (the difference between the pressurizer temperature and the highest temperature in the reactor core) of 30 °C (54 °F). As 345 °C is the boiling point of water at 155 bar, the liquid water is at the edge of a phase change. Thermal transients in the reactor coolant system result in large swings in pressurizer liquid/steam volume, and total pressurizer volume is designed around absorbing these transients without uncovering the heaters or emptying the pressurizer. Pressure transients in the primary coolant system manifest as temperature transients in the pressurizer and are controlled through the use of automatic heaters and water spray, which raise and lower pressurizer temperature, respectively.
The boiling point corresponds to the temperature at which the vapor pressure of the liquid equals the surrounding environmental pressure. Thus, the boiling point is dependent on the pressure. Boiling points may be published with respect to the NIST, USA standard pressure of 101.325 kPa (or 1 atm), or the IUPAC standard pressure of 100.000 kPa. At higher elevations, where the atmospheric pressure is much lower, the boiling point is also lower. The boiling point increases with increased pressure up to the critical point, where the gas and liquid properties become identical. The boiling point cannot be increased beyond the critical point. Likewise, the boiling point decreases with decreasing pressure until the triple point is reached. The boiling point cannot be reduced below the triple point.
The boiling point of a liquid varies depending upon the surrounding environmental pressure. A liquid in a partial vacuum has a lower boiling point than when that liquid is at atmospheric pressure. A liquid at high pressure has a higher boiling point than when that liquid is at atmospheric pressure. For example, water boils at at sea level, but at at altitude. For a given pressure, different liquids will boil at different temperatures.
The heat needed to boil water is thus equivalent to a 540 °C rise in temperature, or about 7 times that needed to raise the temperature of the water from ambient to boiling.
There are three characteristics of liquids which are relevant to the discussion of a BLEVE:Typically, a BLEVE starts with a container of liquid which is held above its normal, atmospheric-pressure boiling temperature. Many substances normally stored as liquids, such as CO, propane, and other similar industrial gases have boiling temperatures, at atmospheric pressure, far below room temperature. In the case of water, a BLEVE could occur if a pressurized chamber of water is heated far beyond the standard . That container, because the boiling water pressurizes it, is capable of holding "liquid" water at very high temperatures.