The normality of a solution is the gram equivalent weight of a solute per liter of solution. It may also be called the equivalent concentration. For example, the concentration of a hydrochloric acid solution might be expressed as 0. A gram equivalent weight or equivalent is a measure of the reactive capacity of a given chemical species ion, molecule, etc.
The equivalent value is determined using the molecular weight and valence of the chemical species.
Normality is the only concentration unit that is reaction dependent. Here are examples of how to calculate the normality of a solution. The easiest way to find normality is from molarity. All you need to know are how many mole of ions dissociate. A normal is one gram equivalent of a solute per liter of solution.
To solve this problem, you need to know the formula for sodium carbonate. Once you realize there are two sodium ions per carbonate ion, the problem is simple:. Find the percent acid eq wt This is essentially a matter of being able to cancel out units to obtain the final result. Remember, if given a value in milliliters mLit's necessary to convert it to liters L.
The only "tricky" concept is realizing the acid and base equivalence factors will be in a ratio. There are specific circumstances when it's preferable to use normality rather than molarity or other unit of concentration of a chemical solution. Normality is not an appropriate unit of concentration in all situations. First, it requires a defined equivalence factor. Second, the normality is not a set value for a chemical solution. Its value can change according to the chemical reaction being examined.
Share Flipboard Email. Anne Marie Helmenstine, Ph. Chemistry Expert. Helmenstine holds a Ph. She has taught science courses at the high school, college, and graduate levels. Facebook Facebook Twitter Twitter. Updated September 25, Key Takeaways Normality is a unit of concentration of a chemical solution expressed as gram equivalent weight of solute per liter of solution. A defined equivalence factor must be used to express concentration. Normality is the only unit of chemical concentration that depends on the chemical reaction being studied.
Normality is not the most common unit of concentration, nor is its use appropriate for all chemical solutions.The unit basis for SI is updated periodically by a panel.
SI concentrations are reported as moles mol or decimal fractions of a mole eg, millimole, micromole per unit volume in liters L. Conventional units are reported as mass eg, grams, milligrams or chemical equivalency eg, milliequivalents per unit volume, which may be in liters or decimal fractions of liters eg, deciliters, milliliters.
An equivalent is a unit that integrates charge and moles; 1 equivalent represents one mole of charges and is calculated by multiplying the number of moles of charged particles in a substance times the valence of that substance.
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Add to Any Platform. Equivalent Subunit. Freezing for water at sea level. Boiling for water at sea level.Nurses must perform dosage calculations when administering medications, feedings and intravenous fluids. Pharmacology math requires the nurse to know systems of measurement and how to convert within those systems of measurement.
Since nurses need to accurately calculate medication dosages, it is essential to understand drug weights and measures. Math computation skills addition, subtraction, division, multiplication, fractions, etc are necessary to calculate medication dosages.
To interpret physician's orders, the nurse must also understand abbreviations used to describe those units of measurement and frequency of administration. Other instances in which the nurse may use math pharmacology includes calculating safe dosages of medications. Nurses may use basic math to determine intake and output. Sometimes it is necessary to convert before one can calculate a problem. When using the metric system, remember the rules for moving the decimal.
If you know one equivalent within a system, then you can use ratio and proportion to solve conversions. Below are some of the most common equivalents used for medication doses. Tip: Your exams may use varied terms to designate the 2 components necessary to calculate the correct dosage to administer.
The key is to clarify the 2 parts of the equation what to give and what is available. Fill in the 2 units of measurement you are dealing with. Make sure both sides of the equation match in terms of the units. As necessary, change mg to mcg, grams to milligrams, etc.
It is easier to calculate if the conversion is changed to the measurement one has "one hand". Cross multiply. Place the X on the left side of the equation: Xtab x 0. Dividing both sides of the equation by 0. The "mg" cancels out leaving 0. Critical vs. Extraneous Information: an important principle in setting up your problem is to identify what is critical information for calculation and what is extraneous to calculating the problem. The nurse has a one gram vial with the following information on the vial: Mix 5.
How many ml will the nurse withdraw from the reconstituted vial? The drip rate is the number of drops per minute to be infused drops per minute. Drip factor of the tubing is found on the manufacturer's packaging.Then, this last equation is converted to milliequivalents mEq by dividing both sides bywhich yields the equation above. As a shortcut, then, the equation can be used remembering that in this instance, the unit of milligram is affixed to the molecular weight.
Of note is that the molecular or atomic weights are usually assigned the unit of gram; however, for milliequivalents we assign the unit of milligram. The weight is not converted from gram to milligram. Once the amount of drug is converted to its metric equivalent, the concentration can be converted to any other unit of concentration, such as percent, ratio strength, or weight per unit volume.
Also, determining the amount, in milliequivalents, of the parent compound eg, potassium chlorideautomatically determines the amount, in milliequivalents, of the individual electrolytes ie, for potassium ion and chloride ion. One milliequivalent of the parent compound will generate one milliequivalent of the cation positively charged electrolyte and one milliequivalent of the anion negatively charged electrolyte.
The patient is to take 40 mEq of potassium in the form of potassium chloride solution. How many milligrams of potassium does this represent? Only gold members can continue reading. Log In or Register to continue. Like this: Like Loading Tags: Pharmacy Calculations Flash Cards.Pure water doesn't exist in nature.
Potassium mEq/L to mmol/L conversion
Even in artificial environments, the purity of water doesn't last much past the opening of the bottle. Water dissolves more substances than any other known liquid. In fact, most people find "pure" water tastes odd. Life depends on water's ability to dissolve many substances, and water's dissolved chemicals determine some of the critical physical conditions of ecosystems.
Two important and interrelated water-related conditions are acidity and alkalinity. The variables used are the volume of acid B used in the titration, the concentration of the acid C athe volume of water in the sample V s and a correction factor CFif necessary. Alkalinity determines how water resists changes in pH, in particular resistance to becoming acidic.
Higher alkalinity means higher resistance to changes in pH. Changes in pH can be devastating to the ecosystem. Many plants and aquatic animals require a very narrow pH range to survive.
Even less pH-sensitive animals suffer if changes in pH impact the food chain. In addition to the natural ecosystem, alkalinity impacts wastewater systems and suitability of water for irrigation. Alkalinity, also referred to as water hardness, impacts home water systems by building mineral deposits in pipes and pans as well as increasing the amount of soap people use by inhibiting lather.
Alkalinity measures the amount of calcium, magnesium and other acid-moderating ions. Alkalinity may be reported in terms of calcium carbonate, CaCO 3. Alkalinity is usually measured and reported in terms of parts per million ppm or grains per gallon.
The recommended method for determining alkalinity uses inflection point titration IPT with sulfuric acid solution. Even when using commercially available 0. Different acid concentrations may be used, especially with lower alkalinities, but the acid must be compared to a standard. Water samples need to represent the environmental conditions, so exposure to sunlight, dust, rain or other contaminants may alter test results. Over time, temperature changes may also affect the sample quality, so samples should be kept at the temperature of the original environment.
For alkalinity tests, filter the water samples through a 0. The micrometer equals 10 -6 meter or one-millionth of a meter. Most tests use a fifty milliliter 50mL sample in a mL beaker, but for low alkalinity samples a larger sample of mL may be used.
The preferred testing method uses a glass buret, but a digital titrator may also be used. Be sure the buret is clean and dry so that the acid solution will not be diluted.
Use standard titration methodology with special care taken around pH 8.The C1V1 = C2V2 Equation Explained
For finding alkalinity in terms of calcium carbonate, take particular care as the sample pH approaches pH 4. The formula for calculating alkalinity finds the ratio of acid to the bicarbonate equivalency point.
The first equation shows the alkalinity in milliequivalents per liter. The following equation combines the alkalinity equation with the conversion factor to calculate the alkalinity in CaCO 3 :. B: The volume of acid used in the titration from the original pH to the equivalency point near pH4.
CF: A correction factor, if necessary. The correction factor for the Hach digital titrator cartridges equals 1. Assume the volume of acid B used equals 12 milliliters of acid, the acid's concentration C a equals 0. If performing the titration with a standard buret, the correction factor CF equals 1.
To calculate the alkalinity, insert these values into the first equation. The calculation becomes:. To calculate alkalinity as calcium carbonate, use this formula to calculate the alkalinity in concentration of calcium carbonate CaCO 3.All Rights Reserved.
The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply. Hottest Questions. Previously Viewed. Unanswered Questions. Wiki User Asked in Cooking Measurements How many tablespoons in 80 meq?
You'll have to explain what a "meq" is. A meq is not an recognised measure of distance. This is equal to 17,24 meq. Asked in Elements and Compounds How many mg of potassium in 40 meq of kcl? There are 15, mg. Asked in Elements and Compounds How many meq of sodium in one teaspoon of salt? If a teaspoon has approx. Meq is a measure of charge. Asked in Health, Vitamins and Supplements, Cooking Measurements 1 meq potassium equals how many mg potassium?
Asked in Salt Sodium Chloride How many meq of sodium chloride in one teaspoon of salt? Asked in Science How many mg is 10 meq?
Milliequivalent is equal to mg. How many meq is equal to 1mg. Asked in Units of Measure How many milligrams is 9. Milli-equivalent refer to a specific substance and must be calculated. It is not a direct relation between milligrams and meq. Asked in Health Is meq bigger tham a mg? Asked in Vitamins and Supplements, Algebra, Elements and Compounds 20 meq is equal to how many mg of potassium?
Potassium has a gram atomic mass of The answer is 0,86 meq. Asked in Elements and Compounds MEq sodium in teaspoon of salt? Asked in Elements and Compounds 1 mmol potassium phosphate in meq? Asked in Synonyms and Antonyms Are cc and mEq synonyms? Asked in Salt Sodium Chloride How many milliequivalents of sodium are in mg of sodium chloride? The value is 5,13 mEq. Asked in Salt Sodium Chloride How many milligrams in a meq of salt?
The answer is 0, g or 58, 4 mg. Asked in Units of Measure, Volume How many milliliters are in 1 milliliter? Asked in Volume How many decaliters are in a milliliter? Trending Questions.The science world is filled with different ways to express the vital concept of concentrationwhich is the amount of something present per unit volume. This "amount" often has units of mass but can include virtually anything that can be quantified: gas particles, photons and more. The volume in question is often a solutionwhich involves a substance called a solute in this context dissolved in a liquid called a solvent.
When solid dissolves in a solvent to create a solution, the concentration of the solution can be expressed in a variety of ways. This relates to the fact that chemicals react with each other not on the basis of mass but on the basis of the ratio of individual "pieces," regardless of size. The concept of moles and equivalents, and thus millimoles and milliequivalentsunderlies this relationship, and it is of vital importance in medicine and clinical pharmacology. In an example of a simple chemical reaction, one atom of potassium K can react with one atom of chlorine Cl to form a molecule of potassium chloride KCl with nothing left over.
But this is not because potassium atoms and chlorine atoms have the same mass. Instead, it is because K and Cl react in a 1-to-1 molar ratio. A mole consists of 6. Every element's molar massor the mass of a single mole in grams is given in the periodic table of elements see the Resources for an online version.
For example, carbon has This means that one mole 1 mol of C atoms has a mass of Because atoms become more massive as you move from lower to higher atomic numbers in the periodic table, molar masses vary enormously, with that of uranium being over times that of hydrogen.
The equivalent unit was introduced to account for the fact that when solutes dissolve in solvent to create a solution, the number of particles dispersed depends on the valence of the solute. This means that KCl has a valence of 2.
This leads to the definition of an equivalent, or specifically a milliequivalent :. This equation assumes that both mass and MW, or molecular weight the same as molar mass but applied to molecules instead of single atomsare given in milligrams. Note: The molar mass of potassium, given in the periodic table, is A solution contains 30 mg of NaCl table salt per mL of solution. Note: the molecular weight of NaCl is Kevin Beck holds a bachelor's degree in physics with minors in math and chemistry from the University of Vermont.
Formerly with ScienceBlogs. More about Kevin and links to his professional work can be found at www. About the Author. Copyright Leaf Group Ltd.