All About the Molarity of Water

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The chemical constituents, composition and important terms associated with the various biochemical and chemical compounds have been a crucial focus of study for a long time. These findings have then allowed us to discover different uses, and properties and uncover new facts which have further contributed to experimentation and helped in the scientific progression of various important resources. One such important resource is water, whose pure water percentage is mostly found in natural reservoirs like lakes, ponds, etc., and groundwater sources. The time encompassing experimentation on water has led to the discovery of important facts like the finding of the molarity of H2O. The finding has also solved various questions regarding how water has molarity and how the association of molarity with water provides it with unique characteristics. The molarity of water(H2O) has also helped us learn about the number of moles a specific sample of water contains. The molarity of pure water is also an important topic of discussion for describing various important properties of water. The other chemical terms like normality, volume percentage, etc., are also some vital derivations that can be obtained from the molarity of water(H2O). 

Molarity of water(H2O)

The molarity of water(H2O) constitutes an important property of water. Molarity is an important measure of a chemical solution’s concentration. Molarity is mainly considered as the number of moles of the solid part in a solvent associated with the quantity of a solution. The fundamental formula for finding molarity is as follows:

Molarity= Moles of solute/litres of a solution

The units for molarity are M or mol/litre, hence the representation of a substance such as water has molarity is by M. M is also the SI unit of Molarity. To find the molarity of a substance we need to find the moles of the substance. The term solute describes the amount of solid substance present as a part of its solution.  The number of moles is found by:

The molecular mass of solute is found by adding the individual atomic masses. Such as the molecular mass of CO2 is found by:

CO2 = (1 * 12) + (2 * 16)= 44 grams

*   The atomic mass of carbon = 12

*   The atomic mass of oxygen = 16

Hence moles of a substance can be found by dividing the given mass of the solute by its calculated molecular mass. In the same manner, the molarity of water can also be calculated. The condition of water has molarity and its finding helps us know about the specific amount of any element or the quantity of compound in a solution. The molarity of water(H2O) also helps to know about the specific volume required for dissolving it. Water has molarity and also responds to finding answers to queries like how the moles of a given sample of water is related to the volume and how moles play a vital part in solving various chemical equations. The molarity of pure water also helps in finding somewhat similar results.

Molarity of pure water

Pure water is mainly termed as a distilled or deionized form of water. It is artificially obtained by evaporation of all the dissolved substances in a water sample. The natural source of pure water is most commonly rainwater as it is formed by condensation by the warmth of the sun after the natural process of evaporation from lakes and other water sources. The molarity of water and the molarity of pure water slightly differ in the fact that in the case of molarity of pure water the total weight of the water sample while calculating moles is already fixed to be 1000 grams or 1 kg. The formula to find the molarity of water applies the same to represent how pure water has molarity. Also, the molarity of pure water can be found using the density of pure water which is 1 g/ml. As molarity is calculated through the use of litres as a unit, hence the conversion to litres is required.

Thus, Density=1g/ml

= 1*1000g/L= 1000g/L

Now we obtain the mass or weight of pure water to be 1000g. Thus now applying the formula to find moles gives,

Moles = mass of pure water or weight of the pure water/molecular mass of pure water

This gives us 1000 grams as the mass of pure water.

And the molecular mass of pure water is, (1*2)+(2*16)= 18 grams.

Hence number or moles= 1000 grams/ 18 grams = 55.56 moles

Hence the molarity

= no of moles/ volume of the solution= 55.56/1= 55.56 M or mol/litre 

Thus the pure water has a molarity of 55.56 mol/litre. 

Conclusion

The article has tried to explain and put forward different issues regarding the Molarity of water(H2O). It has put forward different facts regarding how water has molarity. The molarity of pure water is also explained.