Skip to main content

What is molarity

What is molarity?

It is the most broadly utilized unit and is indicated by M. Molarity is characterized as the quantity of moles of the solute in 1 liter of the arrangement.Thus,
Molarity (M)=No. of moles of solute  
 Volume of solution in litre

Example,
1) 5 moles of solute present in 500ml of solution,what is molarity?
Answer- Molarity (M)= 5 moles
                                            0.5 ltr
                                       = 5 × 10
                                               5
                                       = 10M
(Explained, 500 ml solutions means in litre is 0.5 ltr.)

Calculation of Molarity


For example,
1) 80 gm of NaoH present in 400 ml solution, What is Molarity?
Answer - moles of NaoH = 80 gm     
                                                40 moles
                                             = 2 moles
                       Molarity (M) = 2 moles
                                                  0.4 litre
                                               = 2×10
                                                    4
                                                = 5 M
(Explained, first we find moles of solute formula is,  moles of solute = weight of solute               )
                                     Molecular mass of solute)

Calculation for molarity

For mixing solutions, 
1) 500 ml of 1M sugar solution mix with 1 litre of 2M sugar solution?
Answer- Molarity= Total solute moles           
                                   Total volume of solution
First we find,[1] number of moles of solute
500 ml of 1M sugar solution,(A)=B× C
                                                          = 1×0.5 =0.5
 500 ml of 2M sugar solution,(A)=B×C
                                                          = 2×1= 2
 Molarity= Total solute moles           
                    Total volume of solution
                =(2+0.5) moles
                    1.5 litre
                  = 2.5
                      1.5   
                 = 1.67 M
(A= number of moles of solute, B = Molarity
 C = volume of solution in litre)

General expression to find molarity when similar solutions are mixed=
General expression=
M1,V1,L.                  M1V1+M2V2+M3V3+---------- 
M3,V2 L Resultant V1+V2+V3+---------
M3,B3 L molarity



Comments

Popular posts from this blog

BASICS CHEMISTRY

 CHEMISTRY 1.1 IMPORTANCE OF  BASIC CHEMISTRY Chemistry plays a central role in science and is often intertwined with other branches of science .   Principles of chemistry are applicable in diverse areas, such as weather patterns, functioning of brain and operation of a computer,gs, soa   production in chemical industries, manufacturing fertilizers, alkalies, acids, salts, dyes, polymers, dru ps, detergents, metals, alloys, etc., including new material.  Chemistry contributes in a big way to the national economy. It also plays an important role in meeting human needs for food, healthcare products and other material aimed at improving the quality of life. This is exemplified by the large-scale production of a variety of fertilizers, improved variety of pesticides and insecticides. Basic chemistry  provides methods for the isolation of lifesaving drugs from natural sources and makes possible synthesis of such drugs. Some of these drugs are cis pl...

LAWS OF CHEMICAL COMBINATIONS

  LAWS OF CHEMICAL COMBINATIONS The combination of elements to form compounds is governed by the following five basic laws. 1)  Law of Conservation of  Mass It states that matter can neither be created nor destroyed.This law was put forth by Antoine Lavoisier in 1789. He performed careful experimental studies for combustion reactions for reaching to the above conclusion. This law formed the basis for several later developments in. chemistry Infact, this was the result of exact measurement of masses of reactants and products, and carefully planned experiments performed by Lavoisier . 2)Law of  Definite Proportions This law was given by, a French chemist, Joseph Proust. He stated that a given compound always contains exactly the same proportion of elements by weight. Proust worked with two  samples of cupric carbonate— one of which was of natural origin and the other was synthetic one. He found that the composition of elements presen...

What happens when you put salt in a lemon ?

  What happens when you put salt in a lemon ? Cut 1 Lemon in 4 Parts And Put Some Salt On It.This Trick Will Change Your Life! Ah, the lovely little lemon. Full of nutrition, this bright yellow citrus kills viruses and bacteria. Its fragrance promotes calm and a feeling of well-being while its oil cleans and disinfects. Lemons help us breathe easier and think and sleep better. What's more, that alkalize our bodies to keep body chemistry in balance.   In every detoxifying drink, lemons clean the liver, fight inflammation, regulate blood pressure, and lower cholesterol. Plus, antioxidants and anti-inflammatories found in lemon attack cancers, relieve pain and boost metabolism.   The fruit is good for hair and skin too, from its astringent properties to carcinoma-killing abilities.Here are a couple uses for lemons you might not have thought of yet.   1) Lemon Salt Kitchen Deodorizer The smell of lemon is distinct. Its essential oil contains limonene, an antioxidant. Inh...