What is molarity?

This is very important concept to understand . In every and each step with chemistry and other subject also, in practical you hav to face it. Most of the students have a lot of confusion on it. 

But it is a very simple concept.

Let's start....

The term mole at first you have to know.. 

Mole= molecular weight in gram 

1mole any compound means molecular weight in gram of that compound.

Example:

1 mole NaCl: 

Atomic  wt of Na:23

Atomic  wt of Cl: 35.5

So one Na atom and one Cl atom made a molecule NaCl

So molecular wt of NaCl= 23+35.5= 58.5 

So 1 mole NaCl means 58.5 gram NaCl.

Now come to molaruty: 

The molarity is a unit of strength of a solution like simple a unit gram/liter. 

Solution means solvent +solute 

1 molar solution  means 1 mole in 1000ml solvent.

Example: 1molar NaCl solution 

So 1mole NaCl means 58.5 gram NaCl in 1000ml solvent(water). 

So if any one ask what is the molarity of a solution containing 29.25gm NaCl in 1000 ml water?

It's very simple 

58.5 gram in 1000ml is 1molar so 29.25 gm in 1000 ml means 

(1*23.25)/58.5= .5 molar

It's very easy to understand in this way. 

Try to solve what will be the molarity of the solution containing 117gm NaCl in 500ml water?