Titration is a common laboratory method of quantitative chemical analysis that is used to determine the unknown concentration of a known reactant. Because volume measurements play a key role in titration, it is also known as volumetric analysis.
Standard solution is a chemical term which describes a solution of known concentration.
[see me for the lab, manual on standard soln.]
Mass conc ( conc. In gdm-3 ) :Mass (in grams) of a substance dissolved in 1dm-3 of solution.
Mass conc =
Definition of terms
Molar Conc (conc in moldm-3 ): amount of substance (in moles) present in 1dm3 of solution.
Molar conc =
Note: Molar conc a.k.a MOLARITY (M)
Amount, n (mol)
i.e. molar conc (M) = mass conc/molar mass
Just like in solid
no of mole = mass/molar mass
Conc in moldm-3 =
Conc in gdm-3 molar mass
Concentration is just like Ďsweetnessí of a solution.
Imagine: A sugar solution contains 10.0g of sugar per dm3 of solution and another contains 2.0g sugar per dm3 of solution.
The more concentrated one will be sweeter.
Can you identify the sweeter?
now it follows that:
The conc. of a solution is directly proportional to the amount(mole,n) of substance in solution at constant volume. C α n (V constant).
The conc. (c) of a soln. is inversely proportional to the vol(V) of soln, if the amount(mole/mass) is constant. C α 1/v (n constant).
V V V V V
C C C C C
A solution contains 2.65g of anhydrous Na2CO3 in 200cm3 of solution. Calculate the conc. of the soln in gdm-3 [Na2CO3 = 106]
Hint: Do you notice that the problem is given in 2.65g per 200cm 3 ?.
Just express it in gdm-3 .
I mean gram in 1000cm3