Formula and molecular formula of compounds to simple formulas are of two types:
Simple (empirical) formula
Simple formula, a compound of the type and number of atoms of the element indicates the ratio.
CH2, CH2O, NO2, such as …..
To find a simple formula:
Percent composition by mass of elements in a compound (or a fixed mass ratio) and the atomic mass of elements (or the ratio between the mass of atoms) is enough to know.
Ie a compound in which X and Y’den 7 mass ratio is fixed, the simple compounds
3
What is the formula? (X = 14, y = 12)
To find the number of atomic mass, atomic mass of the element to be divided.
nx = 7 ny = 3 = 0.25 = 0.5
12
written in their place for X0, 5 y0, 25 bulunur.Bu compounds coefficients in 0.25 and a simple formula to divide X2Y is abbreviated.
Molecular Formula
Type and number of atoms of elements in a compound of formula gösterir.Basit expansion coefficient is appropriate.
C2H6O2, C6H12O6 …. like.
To find the molecular formula
Combustion Reactions:
Number of moles of products
The burning of matter and the number of moles of O2
bilinmelidir.Böylece equalized quantities of reaction one mole of atoms of elements found in compounds.
In a given sample composition by mass:
Percent composition by mass of elements (fixed mass ratio)
Atomic mass of elements
Molar mass compounds (or the molar mass compounds, such as for example in ensuring özkütle data)
are known quantities.
Molar mass of one mole of the compounds are known compounds are also found in the number of atoms of elements.
Eg CXHYO2 compound Molu 0.2 0.8 1 mol O2 mol CO2 as the incomplete combustion of organic compounds with 0.8 mol H2O oluşturuyor.Bu What is the molecular formula?
Using data on the reaction of one mole CXHYO2 of the combustion reaction is coefficients.
1 mol 0.8 mol 0.2 mol 0.8 mol
O2 ® CO2 ………. ……… ……… CXHYOZ H2O
1 mol 5 mol 4 4 mol mol
Equivalent to 1 mol CXHYOZ evolved in the combustion reaction is as follows:
1 CXHYOZ 5O2 4CO2 4H2O ®
Equal number of atoms is x = 4, y = 8, the number of oxygen is equalized
Z z = 2 is 4 to 10 = 8.
Coefficients of these values is one mole of atoms in compounds of molecular formula is C4H8O2.










