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Advantages of JSF
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What are the advantages of JSF?
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1 year, 12 months ago
Normality highlights the chemical nature of salts: in solution, salts dissociate into distinct reactive species (ions such as H+, Fe3+, or Cl-). Normality accounts for any discrepancy between the concentrations of the various ionic species in a solution. For example, in a salt such as MgCl2, there are two moles of Cl- for every mole of Mg2+, so the concentration of Cl- is said to be 2 N (read: "two normal"). Further examples are given below. It may also refer to the concentration of a solute in any solution. The normality of a solution is the number of gram equivalent weight of a solute per liter of its solution. The definition of normality depends on the exact reaction intended. For example, hydrochloric acid (HCl) is a monoprotic acid and thus has 1 mol = 1 gram equivalent. One liter of 1 M aqueous solution of HCl acid contains 36.5 grams HCl. It is called 1 N (one normal) solution of HCl. It is given by the following formula:
In contrast, for sulfuric acid, which is diprotic acid, 2 N is usually 1 M, but may be defined as 2 M if pH < 2, where the once-deprotonated species, hydrogen sulfate, does not deprotonate.
A normal is one gram equivalent of a solute per liter of solution. The definition of a gram equivalent varies depending on the type of chemical reaction that is discussed — it can refer to acids, bases, redox species, and ions that will precipitate.
It is critical to note that normality measures a single ion which takes part in an overall solute. For example, one could determine the normality of hydroxide or sodium in an aqueous solution of sodium hydroxide, but the normality of sodium hydroxide itself has no meaning. Nevertheless it is often used to describe solutions of acids or bases, in those cases it is implied that the normality refers to the H+ or OH− ion. For example, 2 Normal sulfuric acid (H2SO4), means that the normality of H+ ions is 2, or that the molarity of the sulfuric acid is 1. Similarly for 1 molar H3PO4 the normality is 3 as it contains three moles of H+ ions for every mole of PO43- .
As ions in solution can react through different pathways, there are three common definitions for normality as a measure of reactive species in solution: In acid-base chemistry, normality is used to express the concentration of protons or hydroxide ions in the solution. Here, the normality differs from the molarity by an integer value - each solute can produce n equivalents of reactive species when dissolved. For example: 1 M aqueous Ca(OH)2 is 2 N (normal) in hydroxide. In redox reactions, normality measures the quantity of oxidizing or reducing agent that can accept or furnish one mole of electrons. Here, the normality scales from the molarity, most commonly, by a fractional value. Calculating the normality of redox species in solution can be challenging. In precipitation reactions, normality measures the concentration of ions which will precipitate in a given reaction. Here, the normality scales from the molarity again by an integer value.
The measure of normality is extremely useful for titrations — given two species that are known to react with a known ratio, one simply needs to scale the volumes of solutions with known normalities to get a complete reaction with the following equation: NaVa=NbVb However, normality cannot reliably represent an unambiguous measure of the concentration of a solution. Since the measure of normality depends on the reaction that the solute participates in, the same concentration of solute can possess two different normalities for two different reactions. For example, Mg2+ is 2 N with respect to a Cl- ion, but it is only 1 N with respect to an O2- ion. Accordingly, normality is no longer used to represent the concentration of a solution as such. Instead, a solution should be labeled according to its molarity, and it is then possible to calculate the normality for a particular titration using the equation above. NIST has also stipulated that this unit is obsolete and recommends discontinuing its use.
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chemistry: what is normality?
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1 year, 11 months ago
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factors influencing gdp
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1 year, 6 months ago
The best time to water the plants is Morning. You may do itn the late evening but in the evening only i.e. between 5:30 to 6:30
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what is the best time to water the plant?
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1 year, 9 months ago
In organic and inorganic chemistry, nucleophilic substitution is a fundamental class of substitution reaction in which an "electron rich" nucleophile selectively bonds with or attacks the positive or partially positive charge of an atom attached to a group or atom called the leaving group; the positive or partially positive atom is referred to as an electrophile.
The most general form for the reaction may be given as Nuc: + R-LG → R-Nuc + LG: The electron pair (:) from the nucleophile (Nuc) attacks the substrate (R-LG) forming a new bond, while the leaving group (LG) departs with an electron pair. The principal product in this case is R-Nuc. The nucleophile may be electrically neutral or negatively charged, whereas the substrate is typically neutral or positively charged. An example of nucleophilic substitution is the hydrolysis of an alkyl bromide, R-Br, under alkaline conditions, where the attacking nucleophile is the OH− and the leaving group is Br-. R-Br + OH− → R-OH + Br− Nucleophilic substitution reactions are commonplace in organic chemistry, and they can be broadly categorised as taking place at a saturated aliphatic carbon or at (less often) a saturated aromatic or other unsaturated carbon centre.
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explain nucleophilic substitution reaction
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1 year, 9 months ago
Mass is the amount of matter present in a body and is an intrinsic property of the body. Mass of an object remains the same always at any place. Weight on the other hand is the force which a given mass feels due to the gravity at its place. Weight is measured in units of Force like Newton (which is the SI unit of Force). If your mass is 60 kgs then your weight is approximately 60 x 10 = 600 Newtons. This is because Force = mass x acceleration (From Newton’s second Law) Thus, weight = mass x acceleration due to gravity If you go to moon your mass remains same, i.e 60 kgs, but your weight becomes less by 1/6 amount, since moon’s gravity is 1/6 that of earth. Mass of a body is measured by balancing it equally with another known amount of mass. You keep known amount of masses like blocks of 1 kg, 2 kg etc on one side till both the sides balance and then add up the numbers on the known side of mass and thus calculate the unknown mass. This works because, when the masses are equal on both the sides of the balance the effect of gravity cancels out for both (i.e weight cancels out) and hence we can calculate the mass on one side of the balance if we know the mass on the other side of the balance. Weight is measured using a scale which effectively measures the pull on the mass exerted by the gravity of the earth.
Mass Weight 1. Is always a constant at any place and time Depends on gravity at the place
kilograms as one might think)
Is measured using balance Is measured using scales
Can never be zero Can also be zero
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Ankur
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what are the differences between the mass of an...
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1 year, 8 months ago
