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Listing A Few Differences Between Normality And Molarity

Normality is a term of chemistry that is used to measure the concentration of a solution. It is denoted by ‘N’. It is the concentration that’s equivalent to the solution. Normality is used in the calculation of titration.

Molarity is the content present in an appropriate volume. It is the no. of solute per litre of volume in litres.

Examples-

  1. Find the molarity if you are given 125mL that also contains 0.5 moles of hydrochloric acid. 

Before we put the numbers in our calculator, it’s better to identify the type of questions and variables and values provided to us. Substitute 0.5 moles in for n, and divide that by the volume. You may be tempted to write 125 mL in the denominator, but that would be incorrect because V should be the volume in litres, not mL. In order to convert 125 mL to litres, you can multiply it by a conversion factor fraction. Because one litre equals 1000 mL, we put 1000 mL on the bottom and one litre on the top. The volume works out to be 0.125 L. 

Now, V is equal to 0.125 L, and that goes in the denominator. Do the division, and the answer works out to be 0.40 moles per litre. In general, the units of molarity are moles per litre.

  1. How many moles of sodium hydroxide are in 38 mL of 0.5 mol/L sodium hydroxide?

The problem is asking us to calculate moles, and it tells us that the volume is 38 mL. In molarity, convert the volume to litre. Next, write down the appropriate equation. M equals n over V. Because we are solving for n, we multiply both sides of the equation by V. On the right side, V divided by V cancels out, which makes n all alone. Now we can write the equation again with n equal to M multiplied by V. Now, put the values of M and V and remember that V is in litres. The unit in the answer has to be units of mole. 

  1. 2.5 mol/L sulfuric acid, how much should you use if you want to make 0.12 moles of sulfuric acid?

We solve this problem by its volume, of course, so the problem is asking us to solve for volume. Next, write down the appropriate equation. We use n is equal to M divided by V because the question would be easily solved by this. It orders to get V all by itself and divide both sides of the equation by M. On the right side, M divides M and cancels out, which makes V all alone. We can also state the statement as V is equal to n divided by M. Finally, change the values and put them on the right variable. We get 0.048 as the answer when 0.12 moles are divided by 2.5 mol/L. And as we are calculating volume, the unit would be litres.

 

Relations between Molarity and Normality-

 

We know the formula of molarity and normality. Now divide normality by molarity. You will get the number of grams equivalent to the number of moles of solute. Since the number of grams is the mass divided by equivalent mass and the number of moles is mass upon molecular mass.

So from N/M and equivalent mass, we get that N is the product of M and the valence factor.

Differences between Normality and molarity- 

Normality –

  • Make use of equivalent weight.
  • It is stated as Normality is a number of equivalents of the solute per litre volume of the solution. 
  • Unit of normality N

Molarity-

  • Make use of molar weight.
  • It is stated as the no. of solute per litre of volume in Litre.
  • Unit of molarity M

The formula of molarity is M is equal to n divided by V, where M is molarity, n is the moles in solute, and V is the volume of the solution in litres.

 

Conclusion 

Even if Molarity is the most important topic in chemistry and is applied in many questions and procedures, it is important to study their integration and the parts that differentiate them because it is no easy feat to understand easily. If you have an interest in the differences between these two portions, you should definitely check out morality and how that is different from all the other kinds.



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Frequently asked questions

Get answers to the most common queries related to the UPSC Examination Preparation.

Name the units used for molarity?

Ans. The units that would be used for molarity are- M or mol/L

What is the formula of molarity?

Ans:  he formula for molarity is the number of moles of solute divided by the volume of the solution in litres....Read full

What is the difference between molarity and normality?

Ans: number of equivalents of the solute per litre volume of the solution. Unit of normality N. Mol...Read full