The chlorination of ethane gives a compound with the percent composition by mass of chlorine in the compound is 71.7%
A) find the molecular formula of this compound
B) write the condensed structural formulas of the isomers of this compound and give their names
C) one of the isomers formed during the chlorination of ethane is a major product. Which one, and why?
(I mainly need an answer to a and b)
THANK YOU
Part c
C2H6 is ethane after chlorination n atoms of hydrogen is replaced by n atoms of chlorine so molecular formula becomes C2H6-nCln
Molar mass=12×2+6-n+35.5×n
=30+34. 5n
%=molar massof Cl÷molarmass of compound×100
%=(35.5n÷(30+34.5n))×100=71.7
n=2
C2H4Cl2 is molecular formula
To find the molecular formula of the compound, we need to determine the empirical formula first and then use the molar mass to find the molecular formula.
A) Finding the empirical formula:
To find the empirical formula, we need to determine the relative amounts of each element in the compound. In this case, we are given that the percent composition by mass of chlorine is 71.7%. This means that in every 100 g of the compound, 71.7 g is chlorine.
Assuming we have a 100g sample of the compound, we can calculate the mass of chlorine:
Mass of chlorine = (71.7/100) * 100 g = 71.7 g
Since there are no other elements mentioned, the remaining 100 - 71.7 = 28.3 g is ethane (C2H6).
Now, let's determine the moles of each element:
Moles of chlorine = 71.7 g / 35.45 g/mol = 2.02 mol
Moles of carbon in ethane = 28.3 g / 12.01 g/mol = 2.36 mol
Moles of hydrogen in ethane = 28.3 g / (1.01 g/mol * 6) = 4.66 mol
Dividing all the moles by the lowest value (which is 2.02 mol), we get:
Moles of chlorine / 2.02 = 1
Moles of carbon / 2.02 = 1.17
Moles of hydrogen / 2.02 = 2.31
Rounding these values to the nearest whole number, we get:
1:1:2
Thus, the empirical formula is CH2Cl.
B) Writing the condensed structural formulas of the isomers:
Now, let's write the condensed structural formulas of the isomers of CH2Cl by considering different arrangements of the atoms.
Isomer 1: CH3Cl
This is the simplest isomer, where the chlorine atom is attached to one of the carbon atoms in ethane. Its name is chloromethane.
Isomer 2: CH2Cl2
In this isomer, both carbon atoms in ethane are bonded to chlorine atoms. Its name is dichloromethane.
Isomer 3: CCl4
In this isomer, all four hydrogen atoms in ethane are replaced by chlorine atoms. Its name is tetrachloromethane or carbon tetrachloride.
C) The major product formed during the chlorination of ethane:
Determining the major product requires understanding the radical chain mechanism of the chlorination reaction in ethane, which involves various steps of initiation, propagation, and termination. Without further information or experimental data, it is difficult to definitively determine the major product. The conditions, temperature, and concentration of reactants can affect the product distribution.