Thermodynamic diagrams are diagrams used by scientists and engineers to represent the thermodynamic states of a material (typically fluid) and the consequences of manipulating this material.
Rules: Violating a rule will result in a ban. Ask homework, exam, lab, and other undergraduate-level questions at otherwise it will be deleted. Discussions on illicit drug synthesis, bomb making, and other illegal activities are not allowed and will lead to a ban. However, academic discussions on pharmaceutical chemistry and the science of explosives are permitted.
![]()
No memes, rage comics, image macros, reaction gifs, or other 'zero-content' material. Likewise, simple pictures of uninteresting and garden variety chemistry-related things are not appreciated. If a caption or explanation is included this helps, but please use your discretion. Before asking about chemical drawing/illustration programs, look at your school's IT/software website and see if they provide an institutional license of ChemDraw (hint: if they have a chemistry department, they will). No physorg, sciencedaily, or other press release aggregator spam!.
Yes links to blogs, images, videos, comics, and infographics are okay especially if they are on your personal website. If you spill/injure yourself contact medical professionals and read the MSDS, do not post to this reddit. For the OSHA chemical data site and for a multicompany MSDS aggregate search. Notes:. Before asking 'What chemical is this?' Any such posts will be deleted. Ask education and jobs questions in the.
Post memes/jokes in. Click for our book recommendations. Past Weekly Topics.
A DePriester Chart DePriester Charts provide an efficient method to find the vapor-liquid equilibrium ratios for different substances at different conditions of pressure and temperature. The original chart was put forth by C.L. DePriester in an article in in 1953.
These have two vertical coordinates, one for, and another for., representing the tendency of a given chemical species to partition itself preferentially between liquid and vapor phases, are plotted in between. Many DePriester charts have been printed for simple hydrocarbons. Example For example, to find the K value of at 100 psia and 60 °F. On the left-hand vertical axis, locate and mark the point containing the pressure 100 psia. On the right-hand vertical axis, locate and mark the point containing the temperature 60°F. Connect the points with a straight line.
Note where the line crosses the methane axis. Read this K-value off the chart (approximately 21.3).
References. – A temperature is an objective comparative measurement of hot or cold. It is measured by a thermometer, several scales and units exist for measuring temperature, the most common being Celsius, Fahrenheit, and, especially in science, Kelvin. Absolute zero is denoted as 0 K on the Kelvin scale, −273.15 °C on the Celsius scale, the kinetic theory offers a valuable but limited account of the behavior of the materials of macroscopic bodies, especially of fluids. Temperature is important in all fields of science including physics, geology, chemistry, atmospheric sciences, medicine. The Celsius scale is used for temperature measurements in most of the world.
Because of the 100 degree interval, it is called a centigrade scale.15, the United States commonly uses the Fahrenheit scale, on which water freezes at 32°F and boils at 212°F at sea-level atmospheric pressure. Many scientific measurements use the Kelvin temperature scale, named in honor of the Scottish physicist who first defined it and it is a thermodynamic or absolute temperature scale.
Its zero point, 0K, is defined to coincide with the coldest physically-possible temperature and its degrees are defined through thermodynamics. The temperature of zero occurs at 0K = −273. For historical reasons, the triple point temperature of water is fixed at 273.16 units of the measurement increment, Temperature is one of the principal quantities in the study of thermodynamics. There is a variety of kinds of temperature scale and it may be convenient to classify them as empirically and theoretically based. Empirical temperature scales are historically older, while theoretically based scales arose in the middle of the nineteenth century, empirically based temperature scales rely directly on measurements of simple physical properties of materials.
For example, the length of a column of mercury, confined in a capillary tube, is dependent largely on temperature. Such scales are only within convenient ranges of temperature. For example, above the point of mercury, a mercury-in-glass thermometer is impracticable. A material is of no use as a thermometer near one of its phase-change temperatures, in spite of these restrictions, most generally used practical thermometers are of the empirically based kind.
Especially, it was used for calorimetry, which contributed greatly to the discovery of thermodynamics, nevertheless, empirical thermometry has serious drawbacks when judged as a basis for theoretical physics. Theoretically based temperature scales are based directly on theoretical arguments, especially those of thermodynamics, kinetic theory and they rely on theoretical properties of idealized devices and materials 2. – Pressure is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure is the relative to the ambient pressure. Various units are used to express pressure, Pressure may also be expressed in terms of standard atmospheric pressure, the atmosphere is equal to this pressure and the torr is defined as 1⁄760 of this. Manometric units such as the centimetre of water, millimetre of mercury, Pressure is the amount of force acting per unit area. The symbol for it is p or P, the IUPAC recommendation for pressure is a lower-case p.
However, upper-case P is widely used. The usage of P vs p depends upon the field in one is working, on the nearby presence of other symbols for quantities such as power and momentum. Mathematically, p = F A where, p is the pressure, F is the normal force and it relates the vector surface element with the normal force acting on it. It is incorrect to say the pressure is directed in such or such direction, the pressure, as a scalar, has no direction.
The force given by the relationship to the quantity has a direction. If we change the orientation of the element, the direction of the normal force changes accordingly. Pressure is distributed to solid boundaries or across arbitrary sections of normal to these boundaries or sections at every point.
It is a parameter in thermodynamics, and it is conjugate to volume. The SI unit for pressure is the pascal, equal to one newton per square metre and this name for the unit was added in 1971, before that, pressure in SI was expressed simply in newtons per square metre. Other units of pressure, such as pounds per square inch, the CGS unit of pressure is the barye, equal to 1 dyncm−2 or 0.1 Pa.
Pressure is sometimes expressed in grams-force or kilograms-force per square centimetre, but using the names kilogram, gram, kilogram-force, or gram-force as units of force is expressly forbidden in SI. The technical atmosphere is 1 kgf/cm2, since a system under pressure has potential to perform work on its surroundings, pressure is a measure of potential energy stored per unit volume. It is therefore related to density and may be expressed in units such as joules per cubic metre.
Similar pressures are given in kilopascals in most other fields, where the prefix is rarely used 3. – Nomograms use a parallel coordinate system invented by dOcagne rather than standard Cartesian coordinates.
A nomogram consists of a set of n scales, one for each variable in an equation. Knowing the values of n-1 variables, the value of the variable can be found, or by fixing the values of some variables.
The result is obtained by laying a straightedge across the values on the scales. The virtual or drawn line created by the straightedge is called a line or isopleth. Nomograms flourished in different contexts for roughly 75 years because they allowed quick. Results from a nomogram are obtained very quickly and reliably by simply drawing one or more lines, the user does not have to know how to solve algebraic equations, look up data in tables, use a slide rule, or substitute numbers into equations to obtain results.
The user does not even need to know the underlying equation the nomogram represents, in addition, nomograms naturally incorporate implicit or explicit domain knowledge into their design. For example, to create larger nomograms for greater accuracy the nomographer usually includes only scale ranges that are reasonable, many nomograms include other useful markings such as reference labels and colored regions. All of these provide useful guideposts to the user, while the slide rule is intended to be a general-purpose device, a nomogram is designed to perform a specific calculation, with tables of values effectively built into the construction of the scales. Nomograms are typically used in applications where the level of accuracy they offer is sufficient, alternatively, a nomogram can be used to check an answer obtained from another, more exact but possibly error-prone calculation. Other types of graphical calculators such as charts, trilinear diagrams. These do not meet the definition of a nomogram as a graphical calculator whose solution is found by the use of one or more linear isopleths. A nomogram for a three-variable equation typically has three scales, although there exist nomograms in which two or even all three scales are common, here two scales represent known values and the third is the scale where the result is read off.
The simplest such equation is u1 + u2 + u3 =0 for the three variables u1, u2 and u3, an example of this type of nomogram is shown on the right, annotated with terms used to describe the parts of a nomogram. More complicated equations can sometimes be expressed as the sum of functions of the three variables. For example, the nomogram at the top of this article could be constructed as a parallel-scale nomogram because it can be expressed as such a sum after taking logarithms of both sides of the equation. The scale for the variable can lie between the other two scales or outside of them 4.
– The International Standard Book Number is a unique numeric commercial book identifier. An ISBN is assigned to each edition and variation of a book, for example, an e-book, a paperback and a hardcover edition of the same book would each have a different ISBN.
The ISBN is 13 digits long if assigned on or after 1 January 2007, the method of assigning an ISBN is nation-based and varies from country to country, often depending on how large the publishing industry is within a country. The initial ISBN configuration of recognition was generated in 1967 based upon the 9-digit Standard Book Numbering created in 1966, the 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108. Occasionally, a book may appear without a printed ISBN if it is printed privately or the author does not follow the usual ISBN procedure, however, this can be rectified later.
Another identifier, the International Standard Serial Number, identifies periodical publications such as magazines, the ISBN configuration of recognition was generated in 1967 in the United Kingdom by David Whitaker and in 1968 in the US by Emery Koltay. The 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108, the United Kingdom continued to use the 9-digit SBN code until 1974. The ISO on-line facility only refers back to 1978, an SBN may be converted to an ISBN by prefixing the digit 0.
For example, the edition of Mr. Reeder Returns, published by Hodder in 1965, has SBN340013818 -340 indicating the publisher,01381 their serial number. This can be converted to ISBN 0-340-01381-8, the check digit does not need to be re-calculated, since 1 January 2007, ISBNs have contained 13 digits, a format that is compatible with Bookland European Article Number EAN-13s. An ISBN is assigned to each edition and variation of a book, for example, an ebook, a paperback, and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, a 13-digit ISBN can be separated into its parts, and when this is done it is customary to separate the parts with hyphens or spaces.
Separating the parts of a 10-digit ISBN is also done with either hyphens or spaces, figuring out how to correctly separate a given ISBN number is complicated, because most of the parts do not use a fixed number of digits. ISBN issuance is country-specific, in that ISBNs are issued by the ISBN registration agency that is responsible for country or territory regardless of the publication language. Some ISBN registration agencies are based in national libraries or within ministries of culture, in other cases, the ISBN registration service is provided by organisations such as bibliographic data providers that are not government funded. In Canada, ISBNs are issued at no cost with the purpose of encouraging Canadian culture. In the United Kingdom, United States, and some countries, where the service is provided by non-government-funded organisations.
Australia, ISBNs are issued by the library services agency Thorpe-Bowker.
Comments are closed.
|
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |