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1 millimole per liter [mmol/l] = 0.001 mol per liter [mol/l]

Initial value

Converted value

moles per meter³ moles per liter moles per centimeter³ moles per millimeter³ kilomoles per meter³ kilomoles per liter kilomoles per centimeter³ kilomoles per millimeter³ millimoles per meter³ millimoles per liter millimoles per centimeter³ millimoles per millimeter³ moles per cubic. decimeter molar millimolar micromolar nanomolar Picomolar Femtomolar Attomolar zeptomolar yoctomolar

Mass concentration in solution

More about molar concentration

General information

The concentration of a solution can be measured different ways, for example, as the ratio of the mass of the solute to the total volume of the solution. In this article we will look at molar concentration, which is measured as the ratio between the amount of substance in moles to the total volume of the solution. In our case, the substance is the soluble substance, and we measure the volume for the entire solution, even if other substances are dissolved in it. Quantity of substance is the number of elementary components, such as atoms or molecules of a substance. Since even in small amounts of a substance it is usually big number elementary components, then special units, moles, are used to measure the amount of a substance. One mole equal to the number of atoms in 12 g of carbon-12, that is, approximately 6 x 10²³ atoms.

It is convenient to use moles if we are working with an amount of a substance so small that its amount can easily be measured with home or industrial instruments. Otherwise you would have to work with very large numbers, which is inconvenient, or with very small weight or volume, which is difficult to find without specialized laboratory equipment. The most common particles used when working with moles are atoms, although it is possible to use other particles, such as molecules or electrons. It should be remembered that if non-atoms are used, this must be indicated. Sometimes molar concentration is also called molarity.

Molarity should not be confused with molality. Unlike molarity, molality is the ratio of the amount of solute to the mass of the solvent, rather than to the mass of the entire solution. When the solvent is water and the amount of solute compared to the amount of water is small, then molarity and molality are similar in meaning, but otherwise they are usually different.

Factors affecting molar concentration

Molar concentration depends on temperature, although this dependence is stronger for some solutions and weaker for other solutions, depending on what substances are dissolved in them. Some solvents expand when the temperature increases. In this case, if the substances dissolved in these solvents do not expand with the solvent, then the molar concentration of the entire solution decreases. On the other hand, in some cases, with increasing temperature, the solvent evaporates, but the amount of soluble substance does not change - in this case, the concentration of the solution will increase. Sometimes the opposite happens. Sometimes a change in temperature affects how the solute dissolves. For example, some or all of the solute stops dissolving and the concentration of the solution decreases.

Units

Molar concentration is measured in moles per unit volume, such as moles per liter or moles per unit volume. cubic meter. Moles per cubic meter is an SI unit. Molarity can also be measured using other units of volume.

How to find molar concentration

To find the molar concentration, you need to know the amount and volume of the substance. The amount of a substance can be calculated using the chemical formula of that substance and information about the total mass of that substance in solution. That is, to find out the amount of solution in moles, we find out from the periodic table the atomic mass of each atom in the solution, and then divide the total mass of the substance by the total atomic mass of the atoms in the molecule. Before adding atomic masses together, we should make sure that we multiply the mass of each atom by the number of atoms in the molecule we are considering.

You can also perform calculations in reverse order. If the molar concentration of the solution and the formula of the soluble substance are known, then you can find out the amount of solvent in the solution, in moles and grams.

Examples

Let's find the molarity of a solution of 20 liters of water and 3 tablespoons of soda. One tablespoon contains approximately 17 grams, and three tablespoons contain 51 grams. Soda is sodium bicarbonate, the formula of which is NaHCO₃. In this example, we will use atoms to calculate molarity, so we will find the atomic mass of the constituents sodium (Na), hydrogen (H), carbon (C), and oxygen (O).

Na: 22.989769
H: 1.00794
C: 12.0107
O: 15.9994

Since oxygen in the formula is O₃, it is necessary to multiply the atomic mass of oxygen by 3. We get 47.9982. Now let's add up the masses of all the atoms and get 84.006609. Atomic mass is indicated in the periodic table in atomic mass units, or a. e.m. Our calculations are also in these units. One a. e.m. is equal to the mass of one mole of a substance in grams. That is, in our example, the mass of one mole of NaHCO₃ is equal to 84.006609 grams. In our problem - 51 grams of soda. Let's find the molar mass by dividing 51 grams by the mass of one mole, that is, by 84 grams, and we get 0.6 moles.

It turns out that our solution is 0.6 moles of soda dissolved in 20 liters of water. Let's divide this amount of soda by the total volume of the solution, that is, 0.6 mol / 20 l = 0.03 mol/l. Since the solution was used a large number of solvent and a small amount of soluble substance, then its concentration is low.

Let's look at another example. Let's find the molar concentration of one piece of sugar in a cup of tea. Table sugar consists of sucrose. First, let's find the weight of one mole of sucrose, the formula of which is C₁₂H₂₂O₁₁. Using the periodic table, we find atomic masses and determine the mass of one mole of sucrose: 12×12 + 22×1 + 11×16 = 342 grams. There are 4 grams of sugar in one cube, which gives us 4/342 = 0.01 moles. There are about 237 milliliters of tea in one cup, which means the sugar concentration in one cup of tea is 0.01 moles / 237 milliliters × 1000 (to convert milliliters to liters) = 0.049 moles per liter.

Application

Molar concentration is widely used in calculations involving chemical reactions. The branch of chemistry in which the relationships between substances in chemical reactions are calculated and often work with moles is called stoichiometry. The molar concentration can be found by chemical formula the final product, which then becomes a soluble substance, as in the example with a soda solution, but you can also first find this substance by the formulas of the chemical reaction during which it is formed. To do this, you need to know the formulas of the substances involved in this chemical reaction. Having solved the equation of a chemical reaction, we find out the formula of the molecule of the solute, and then we find the mass of the molecule and the molar concentration using the periodic table, as in the examples above. Of course, you can perform calculations in reverse order, using information about the molar concentration of the substance.

Let's look at a simple example. This time we'll mix baking soda and vinegar to see what's interesting. chemical reaction. Both vinegar and baking soda are easy to find - you probably have them in your kitchen. As mentioned above, the formula of soda is NaHCO₃. Vinegar is not a pure substance, but a 5% solution of acetic acid in water. The formula of acetic acid is CH₃COOH. The concentration of acetic acid in vinegar may be more or less than 5%, depending on the manufacturer and the country in which it is made, as in different countries The concentration of vinegar varies. In this experiment, you don't have to worry about chemical reactions between water and other substances, since water doesn't react with baking soda. We only care about the volume of water when we later calculate the concentration of the solution.

First, let's solve the equation for the chemical reaction between soda and acetic acid:

NaHCO₃ + CH₃COOH → NaC₂H₃O₂ + H₂CO₃

The reaction product is H₂CO₃, a substance that, due to its low stability, again enters into a chemical reaction.

H₂CO₃ → H₂O + CO₂

As a result of the reaction we obtain water (H₂O), carbon dioxide(CO₂) and sodium acetate (NaC₂H₃O₂). Let's mix the resulting sodium acetate with water and find the molar concentration of this solution, just as before we found the concentration of sugar in tea and the concentration of soda in water. When calculating the volume of water, it is necessary to take into account the water in which it is dissolved. acetic acid. Sodium acetate is an interesting substance. It is used in chemical warmers, such as hand warmers.

When using stoichiometry to calculate the amount of substances involved in a chemical reaction, or reaction products for which we will later find the molar concentration, it should be noted that only limited quantity substances may react with other substances. This also affects the quantity of the final product. If the molar concentration is known, then, on the contrary, the amount of starting products can be determined by reverse calculation. This method is often used in practice, in calculations related to chemical reactions.

When using recipes, whether in cooking, making medicine, or creating the perfect environment for aquarium fish, you need to know the concentration. IN Everyday life It is often more convenient to use grams, but in pharmaceuticals and chemistry molar concentrations are more often used.

In pharmaceuticals

When creating drugs, molar concentration is very important because it determines how the drug affects the body. If the concentration is too high, the drugs can even be fatal. On the other hand, if the concentration is too low, the drug is ineffective. In addition, concentration is important in the exchange of fluids across cell membranes in the body. When determining the concentration of a liquid that must either pass or, conversely, not pass through membranes, either the molar concentration is used or it is used to find osmotic concentration. Osmotic concentration is used more often than molar concentration. If the concentration of a substance, such as a drug, is higher on one side of the membrane compared to the concentration on the other side of the membrane, such as inside the eye, then the more concentrated solution will move across the membrane to where the concentration is lower. This flow of solution through the membrane is often problematic. For example, if fluid moves into a cell, such as into a blood cell, it is possible that the membrane will become damaged and rupture due to this fluid overflow. Leakage of fluid from the cell is also problematic, since this will impair the functioning of the cell. It is desirable to prevent any drug-induced flow of fluid through the membrane out of the cell or into the cell, and to do this, try to make the concentration of the drug similar to the concentration of fluid in the body, for example in the blood.

It is worth noting that in some cases the molar and osmotic concentrations are equal, but this is not always the case. This depends on whether the substance dissolved in water has broken down into ions during the process electrolytic dissociation. When calculating osmotic concentration, particles in general are taken into account, while when calculating molar concentration, only certain particles, such as molecules, are taken into account. Therefore, if, for example, we are working with molecules, but the substance has broken up into ions, then there will be fewer molecules total number particles (including molecules and ions), and therefore the molar concentration will be lower than the osmotic one. To convert molar concentration to osmotic concentration, you need to know physical properties solution.

In the manufacture of medicines, pharmacists also take into account tonicity solution. Tonicity is a property of a solution that depends on concentration. Unlike osmotic concentration, tonicity is the concentration of substances that the membrane does not allow through. The process of osmosis causes solutions of higher concentration to move into solutions of lower concentration, but if the membrane prevents this movement by not allowing the solution to pass through, then pressure occurs on the membrane. This kind of pressure is usually problematic. If a drug is intended to enter the blood or other body fluid, then the tonicity of that drug must be balanced with the tonicity of the body fluid to avoid osmotic pressure on membranes in the body.

To balance the tonicity, medications often dissolved in isotonic solution. An isotonic solution is a solution of table salt (NaCL) in water at a concentration that balances the tonicity of the fluid in the body and the tonicity of the mixture of this solution and the drug. Typically, the isotonic solution is stored in sterile containers and infused intravenously. Sometimes it is used in pure form, and sometimes - as a mixture with medicine.

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analysis category: Biochemical laboratory tests
branches of medicine: Hematology; Laboratory diagnostics; Nephrology; Oncology; Rheumatology

Clinics in St. Petersburg where this test is performed for adults (249)

Clinics in St. Petersburg where this test is performed for children (129)

Description

Uric acid - is formed during the metabolism of purines, during the breakdown nucleic acids. When the metabolism of purine bases is disrupted, the level increases uric acid in the body, its concentration in the blood and other biological fluids, deposition occurs in tissues in the form of salts - urates. Serum uric acid levels are used to diagnose gout, evaluate kidney function, diagnose urolithiasis, .

Material for research

The patient's blood is taken from a vein. Blood plasma is used for analysis.

Readiness of results

Within 1 business day. Urgent execution 2-3 hours.

Interpretation of the data obtained

Units of measurement: µmol/l, mg/dl.
Conversion factor: mg/dL x 59.5 = µmol/L.
Normal values: children under 14 years old 120 - 320 µmol/l, women over 14 years old 150 - 350 µmol/l, men over 14 years old 210 - 420 µmol/l.

Increased uric acid levels:
gout, Lesch-Nyhan syndrome (genetically determined deficiency of the enzyme hypoxanthine-guanine phosphoribosyl transferase - GGPT), leukemia, myeloma, lymphoma, renal failure, toxicosis of pregnant women, prolonged fasting, alcohol consumption, taking salicylates, diuretics, cytostatics, increased exercise stress, diet, rich purine bases, idiopathic familial hypouricemia, increased protein catabolism with oncological diseases, pernicious (B12 - deficiency) anemia.

Reducing uric acid levels:
Konovalov-Wilson disease (hepatocerebral dystrophy), Fanconi syndrome, taking allopurinol, radiocontrast agents, glucocorticoids, azathioprine, xanthinuria, Hodgkin's disease.

Preparing for the study

The study is carried out in the morning strictly on an empty stomach, i.e. between last appointment food must pass at least 12 hours, 1-2 days before blood donation it is necessary to limit intake fatty foods, alcohol, adhere to a low-purine diet. Immediately before donating blood, you must refrain from smoking for 1-2 hours, do not drink juice, tea, coffee (especially with sugar), you can drink clean still water. Eliminate physical stress.

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1 microgram per liter [µg/l] = 1000 nanograms per liter [ng/l]

Initial value

Converted value

kilogram per cubic meter kilogram per cubic centimeter gram per cubic meter gram per cubic centimeter gram per cubic millimeter milligram per cubic meter milligram per cubic centimeter milligram per cubic millimeter exagrams per liter petagrams per liter teragrams per liter gigagrams per liter megagrams per liter kilogram per liter hectograms per liter decagrams per liter grams per liter decigrams per liter centigrams per liter milligrams per liter micrograms per liter nanograms per liter picograms per liter femtograms per liter attograms per liter pound per cubic inch pound per cubic foot pound per cubic yard pound per gallon (USA ) pound per gallon (UK) ounce per cubic inch ounce per cubic foot ounce per gallon (US) ounce per gallon (UK) grain per gallon (US) grain per gallon (UK) grain per cubic foot short ton per cubic yard long ton per cubic yard slug per cubic foot average density of the Earth slug per cubic inch slug per cubic yard Planck density

More about density

General information

Density is a property that determines how much of a substance by mass is per unit volume. In the SI system, density is measured in kg/m³, but other units are also used, such as g/cm³, kg/l and others. In everyday life, two equivalent quantities are most often used: g/cm³ and kg/ml.

Factors affecting the density of a substance

The density of the same substance depends on temperature and pressure. Typically, the higher the pressure, the more tightly the molecules are compacted, increasing density. In most cases, an increase in temperature, on the contrary, increases the distance between molecules and reduces density. In some cases, this relationship is reversed. The density of ice, for example, is less than the density of water, despite the fact that ice colder than water. This can be explained by the molecular structure of ice. Many substances transition from liquid to solid state of aggregation change the molecular structure so that the distance between molecules decreases and the density, accordingly, increases. During the formation of ice, the molecules line up in a crystalline structure and the distance between them, on the contrary, increases. At the same time, the attraction between the molecules also changes, the density decreases, and the volume increases. In winter, you must not forget about this property of ice - if the water in the water pipes freezes, they can break.

Density of water

If the density of the material from which the object is made is greater than the density of water, then it is completely immersed in water. Materials with a density lower than that of water, on the contrary, float to the surface. A good example is ice, which is less dense than water, floating in a glass on the surface of water and other drinks that are mostly water. We often use this property of substances in everyday life. For example, when constructing ship hulls, materials with a density higher than the density of water are used. Since materials with a density higher than the density of water sink, air-filled cavities are always created in the ship's hull, since the density of air is much lower than the density of water. On the other hand, sometimes it is necessary for an object to sink in water - for this purpose, materials with a higher density than water are chosen. For example, in order to sink light bait to a sufficient depth while fishing, anglers tie a sinker made of high-density materials, such as lead, to the fishing line.

Oil, grease and petroleum remain on the surface of the water because their density is lower than that of water. Thanks to this property, oil spilled in the ocean is much easier to clean up. If it mixed with water or sank to the seabed, it would cause even more damage to the marine ecosystem. This property is also used in cooking, but not of oil, of course, but of fat. For example, it is very easy to remove excess fat from the soup as it floats to the surface. If you cool the soup in the refrigerator, the fat hardens, and it is even easier to remove it from the surface with a spoon, slotted spoon, or even a fork. In the same way it is removed from jellied meat and aspic. This reduces the calorie content and cholesterol content of the product.

Information about the density of liquids is also used during the preparation of drinks. Multilayer cocktails are made from liquids of different densities. Typically, liquids with lower densities are carefully poured onto liquids of higher density. high density. You can also use a glass cocktail stick or bar spoon and slowly pour the liquid over it. If you take your time and do everything carefully, you will get a beautiful multi-layered drink. This method can also be used with jellies or jellied dishes, although if time permits, it is easier to chill each layer separately, pouring a new layer only after the bottom layer has set.

In some cases, the lower density of fat, on the contrary, interferes. Products with a high fat content often do not mix well with water and form a separate layer, thereby deteriorating not only the appearance, but also the taste of the product. For example, in cold desserts and smoothies, high-fat dairy products are sometimes separated from low-fat dairy products such as water, ice and fruit.

Density of salt water

The density of water depends on the content of impurities in it. Rarely found in nature and in everyday life pure water H 2 O without impurities - most often it contains salts. Good example - sea water. Its density is higher than that of fresh water, so fresh water usually “floats” on the surface of salt water. Of course, see this phenomenon in normal conditions difficult, but if fresh water is enclosed in a shell, for example in a rubber ball, then this is clearly visible, since this ball floats to the surface. Our body is also a kind of shell filled fresh water. We are made up of 45% to 75% water - this percentage decreases with age and with increasing weight and amount of body fat. Fat content of at least 5% of body weight. U healthy people in the body up to 10% fat if they play a lot of sports, up to 20% if they have normal weight, and 25% or higher if they are obese.

If we try not to swim, but simply float on the surface of the water, we will notice that it is easier to do this in salt water, since its density is higher than the density of fresh water and the fat contained in our body. The Dead Sea's salt concentration is 7 times the average salt concentration in the world's oceans, and it is famous around the world for allowing people to easily float on the surface of the water without drowning. Although, it is a mistake to think that it is impossible to die in this sea. In fact, people die in this sea every year. High content salt makes water dangerous if it gets into your mouth, nose, or eyes. If you swallow such water, you can get chemical burn- V severe cases such unlucky swimmers are hospitalized.

Air density

Just as in the case of water, bodies with a density lower than the density of air have positive buoyancy, that is, they take off. A good example of such a substance is helium. Its density is 0.000178 g/cm³, while the density of air is approximately 0.001293 g/cm³. You can see helium soar in the air if you fill a balloon with it.

The density of air decreases as its temperature increases. This property of hot air is used in balloons. The balloon in the photograph at the ancient Mayan city of Teotihuocan in Mexico is filled with hot air that is less dense than the surrounding cold morning air. That is why the ball flies at a fairly high altitude. While the ball flies over the pyramids, the air in it cools down and is heated again using a gas burner.

Density calculation

Often the density of substances is indicated for standard conditions, that is, for a temperature of 0 °C and a pressure of 100 kPa. In educational and reference books you can usually find such densities for substances that are often found in nature. Some examples are shown in the table below. In some cases, the table is not enough and the density must be calculated manually. In this case, the mass is divided by the volume of the body. The mass can be easily found using a scale. To find out the volume of a body of a standard geometric shape, you can use formulas to calculate volume. The volume of liquids and solids can be found by filling a measuring cup with the substance. For more complex calculations, the liquid displacement method is used.

Liquid displacement method

To calculate the volume in this way, first pour a certain amount of water into a measuring vessel and place the body whose volume needs to be calculated until it is completely immersed. The volume of a body is equal to the difference in the volume of water without the body and with it. It is believed that this rule was derived by Archimedes. Volume can be measured in this way only if the body does not absorb water and does not deteriorate from water. For example, we will not measure the volume of a camera or fabric product using the liquid displacement method.

It is unknown to what extent this legend reflects actual events, but it is believed that King Hiero II gave Archimedes the task of determining whether his crown was made of pure gold. The king suspected that his jeweler had stolen some of the gold allocated for the crown and instead made the crown from a cheaper alloy. Archimedes could easily determine this volume by melting the crown, but the king ordered him to find a way to do this without damaging the crown. It is believed that Archimedes found the solution to this problem while taking a bath. Having immersed himself in water, he noticed that his body had displaced a certain amount of water, and realized that the volume of displaced water was equal to the volume of the body in the water.

Hollow bodies

Some natural and artificial materials consist of particles that are hollow inside, or particles so small that they behave like liquids. In the second case, an empty space remains between the particles, filled with air, liquid, or other substance. Sometimes this place remains empty, that is, it is filled with a vacuum. Examples of such substances are sand, salt, grain, snow and gravel. The volume of such materials can be determined by measuring the total volume and subtracting from it the volume of voids determined by geometric calculations. This method is convenient if the shape of the particles is more or less uniform.

For some materials, the amount of empty space depends on how tightly the particles are packed. This complicates calculations because it is not always easy to determine how much empty space there is between particles.

Table of densities of substances commonly found in nature

Substance	Density, g/cm³
Liquids
Water at 20°C	0,998
Water at 4°C	1,000
Petrol	0,700
Milk	1,03
Mercury	13,6
Solids
Ice at 0°C	0,917
Magnesium	1,738
Aluminum	2,7
Iron	7,874
Copper	8,96
Lead	11,34
Uranus	19,10
Gold	19,30
Platinum	21,45
Osmium	22,59
Gases at normal temperature and pressure
Hydrogen	0,00009
Helium	0,00018
Carbon monoxide	0,00125
Nitrogen	0,001251
Air	0,001293
Carbon dioxide	0,001977

Density and mass

Some industries, such as aviation, require materials that are as light as possible. Since low-density materials also have low mass, in such situations they try to use materials with the lowest density. For example, the density of aluminum is only 2.7 g/cm³, while the density of steel is from 7.75 to 8.05 g/cm³. It is due to the low density that 80% of aircraft bodies use aluminum and its alloys. Of course, you should not forget about strength - today few people make airplanes from wood, leather, and other lightweight but low-strength materials.

Black holes

On the other hand, the higher the mass of a substance per given volume, the higher the density. Black holes - an example physical bodies with a very small volume and enormous mass, and, accordingly, enormous density. Such an astronomical body absorbs light and other bodies that are close enough to it. The largest black holes are called supermassive.

Creatinine is the anhydride of creatine (methylguanidinacetic acid) and is an elimination form formed in muscle tissue. Creatine is synthesized in the liver, and after release, 98% of it enters muscle tissue, where phosphorylation occurs, and in this form plays an important role in storing muscle energy. When this muscle energy is needed to carry out metabolic processes, phosphocreatine is broken down into creatinine. The amount of creatine converted into creatinine is maintained at a constant level, which is directly related to muscle mass body. In men, 1.5% of creatine reserves are converted to creatinine daily. Creatine obtained from food (especially meat) increases creatine and creatinine stores. Decreasing protein intake lowers creatinine levels in the absence of the amino acids arginine and glycine, precursors to creatine. Creatinine is a stable nitrogenous constituent of the blood, unaffected by most foods, exercise, circadian rhythms or other biological constants, and is associated with muscle metabolism. Impaired renal function reduces creatinine excretion, causing an increase in serum creatinine levels. Thus, creatinine concentrations approximately characterize the level of glomerular filtration. The main value of determining serum creatinine is the diagnosis of renal failure. Serum creatinine is a more specific and sensitive indicator of renal function than urea. However, in chronic kidney disease, it is used to determine both serum creatinine and urea, in combination with blood urea nitrogen (BUN).

Material: deoxygenated blood.

Test tube: vacutainer with/without anticoagulant with/without gel phase.

Processing conditions and sample stability: serum remains stable for 7 days at

2-8 °C. Archived serum can be stored at -20°C for 1 month. Must be avoided

defrosting and re-freezing twice!

Method: kinetic.

Analyzer: Cobas 6000 (with 501 modules).

Test systems: Roche Diagnostics (Switzerland).

Reference values in the SYNEVO Ukraine laboratory, µmol/l:

Children:

Newborns: 21.0-75.0.

2-12 months: 15.0-37.0.

1-3 years: 21.0-36.0.

3-5 years: 27.0-42.0.

5-7 years: 28.0-52.0.

7-9 years: 35.0-53.0.

9-11 years: 34.0-65.0.

11-13 years: 46.0-70.0.

13-15 years: 50.0-77.0.

Women: 44.0-80.0.

Men: 62.0-106.0.

Conversion factor:

µmol/l x 0.0113 = mg/dl.

µmol/l x 0.001 = mmol/l.

Main indications for the purpose of the analysis: serum creatinine is determined at the first examination in patients without or with symptoms, in patients with symptoms of urinary tract diseases, in patients with arterial hypertension, with acute and chronic renal diseases, non-renal diseases, diarrhea, vomiting, profuse sweating, with acute illnesses, after surgery or in patients in need of intensive care, for sepsis, shock, multiple injuries, hemodialysis, for metabolic disorders (diabetes mellitus, hyperuricemia), during pregnancy, diseases with increased protein metabolism (multiple myeloma, acromegaly), during treatment with nephrotoxic medications.

Interpretation of results

Increased level:

Acute or chronic diseases kidney

Obstruction urinary tract(postrenal azotemia).

Reduced renal perfusion (prerenal azotemia).

Congestive heart failure.

Shock states.

Dehydration.

Muscle diseases (myasthenia gravis, muscular dystrophy, polio).

Rhabdomyolysis.

Hyperthyroidism.

Acromegaly.

Reduced level:

Pregnancy.

Decreased muscle mass.

Lack of protein in the diet.

Severe liver diseases.

Interfering factors:

Higher levels are recorded in men and in individuals with large muscle mass; the same creatinine concentrations in young and elderly people do not mean the same level of glomerular filtration (in old age, creatinine clearance decreases and creatinine formation decreases). In conditions of decreased renal perfusion, increases in serum creatinine occur more slowly than increases in urea levels. Since there is a forced decline in kidney function by 50% with an increase in creatinine values, creatinine cannot be considered as a sensitive indicator for mild or moderate kidney damage.

Serum creatinine levels can be used to estimate glomerular filtration rate only under conditions of balance, when the rate of creatinine synthesis is equal to the rate of its elimination. To check for this condition, two determinations are required 24 hours apart; Differences of more than 10% may indicate the absence of such balance. In renal impairment, glomerular filtration rate may be overestimated by serum creatinine because creatinine elimination is independent of glomerular filtration and tubular secretion, and creatinine is also eliminated through the intestinal mucosa, presumably metabolized by bacterial creatine kinases.

Medicines

Raise:

Acebutolol, ascorbic acid, nalidixic acid, acyclovir, alkaline antacids, amiodarone, amphotericin B, asparaginase, aspirin, azithromycin, barbiturates, captopril, carbamazepine, cefazolin, cefixime, cefotetan, cefoxitin, ceftriaxone, cefuroxime, cimetidine, ciprofloc sacin, clarithromycin, diclofenac, diuretics, enalapril, ethambutol, gentamicin, streptokinase, streptomycin, triamterene, triazolam, trimethoprim, vasopressin.

Reduce: glucocorticoids

Convert millimoles per liter to micromoles per liter (mmol/L to µmol/L):

Select the desired category from the list, in in this case"Molar concentration".
Enter the value to be converted. Basic arithmetic operations such as addition (+), subtraction (-), multiplication (*, x), division (/, :, ÷), exponent (^), parentheses and pi (pi) are already supported at this time .
From the list, select the unit of measurement for the value to be converted, in this case "millimoles per liter [mmol/l]".
Finally, select the unit you want the value to be converted to, in this case "micromoles per liter [μmol/L]".
After displaying the result of an operation, and whenever appropriate, an option appears to round the result to a certain number of decimal places.

With this calculator, you can enter the value to be converted along with the original measurement unit, for example, "342 millimoles per liter." In this case, you can use either the full name of the unit of measurement or its abbreviation, for example, “millimoles per liter” or “mmol/l”. After entering the unit of measurement you want to convert, the calculator determines its category, in this case "Molar Concentration". It then converts the entered value into all the appropriate units of measurement that it knows. In the list of results you will undoubtedly find the converted value you need. Alternatively, the value to be converted can be entered as follows: "33 mmol/l to µmol/l" or "15 mmol/l how many µmol/l" or "1 millimoles per liter -> micromoles per liter" or "54 mmol/l = µmol/l" or "44 millimoles per liter to µmol/l" or "15 mmol/l to micromoles per liter" or 2 millimole per liter how many micromoles per liter". In this case, the calculator will also immediately understand into which unit of measurement the original value needs to be converted. Regardless of which of these options is used, the need for a complex search is eliminated desired value in long selection lists with countless categories and countless units of measurement supported. All this is done for us by a calculator that copes with its task in a split second.

In addition, the calculator allows you to use mathematical formulas. As a result, not only numbers such as "(1 * 56) mmol/l" are taken into account. You can even use multiple units of measurement directly in the conversion field. For example, such a combination might look like this: “342 millimoles per liter + 1026 micromoles per liter” or “92mm x 29cm x 24dm = ? cm^3”. The units of measurement combined in this way must naturally correspond to each other and make sense in a given combination.

If you check the box next to the "Numbers in scientific notation" option, the answer will be represented as an exponential function. For example, 1.807530847749 × 1028. In this form, the representation of the number is divided into an exponent, here 28, and the actual number, here 1.807530847749. In devices that have disabilities display numbers (for example, pocket calculators), and also use the method of writing numbers 1,807 530 847 749 E+28. In particular, it makes it easier to see very large and very small numbers. If this cell is unchecked, the result is displayed using the normal way of writing numbers. In the example above, it would look like this: 18,075,308,477,490,000,000,000,000,000 Regardless of the presentation of the result, the maximum accuracy of this calculator is 14 decimal places. This accuracy should be sufficient for most purposes.

How many micromoles per liter are in 1 millimole per liter?

1 millimole per liter [mmol/l] = 1,000 micromoles per liter [µmol/l] - Measurement calculator which, among other things, can be used to convert millimoles per liter to micromoles per liter.