Name: Redox Reactions as a Basis for Titration
Uploaded: 2019-07-19
Duration: 7 min 17 s
Description: This video will help us learn about how redox indicators like potassium permanganate or diphenylamine are used to indicate the completion of a redox reaction...

Question

Chemical analysis of a carbon compound gave the following percentage composition by weight of the elements present, carbon

= 10.06 %

, hydrogen

= 0.84 %

, chlorine

= 89.10 %

, Calculate the empirical formula of the compound.

Accepted Answer

When dealing with mass percentages is to pick a sample of your compound and determine how many moles of each element it contains.

To make the calculations easier, you can pick a $100.0 g$ sample of chloroform and use its percent concentration by mass to find that it contains.

$89.1 g$ → chlorine
$0.84 g$ → hydrogen
$10.06 g$ → carbon

Next, use the molar masses of the three elements to find how many moles of each you have in this sample.

For $Cl : 89.1 g \times \frac{1 mole Cl}{35.5 g} = 2.50 moles C$
For $H : 0.84 g \times \frac{1 mole H}{1 g} = 0.84 moles H$
For $C : 10.06 g \times \frac{1 mole C}{12 g} = 0.83 moles C$

To find the mole ratios that exist between the elements in the compound, divided these values by the smallest one.

For $Cl : \frac{2.50 moles}{0.83 moles} = 3.01 \approx 3$ .
For $H : \frac{0.84 moles}{0.83 moles} = 1.01 \approx 1 .$
For $C : \frac{0.83 moles}{0.83 moles} = 1$ .

The compound's empirical formula, which tells you what the smallest whole number ratio that exists between the elements that make up a compound is, will thus be

$C_{1} H_{1} {Cl}_{3} \Rightarrow {CHCl}_{3}$ .

Chemical analysis of a carbon compound gave the following percentage composition by weight of the elements present, carbon $= 10.06 %$ , hydrogen $= 0.84 %$ , chlorine $= 89.10 %$ , Calculate the empirical formula of the compound.

Important Questions on Stoichiometry

Learn and Prepare for any exam you want !

Chemical analysis of a carbon compound gave the following percentage composition by weight of the elements present, carbon= 10.06%, hydrogen = 0.84 %, chlorine = 89.10%, Calculate the empirical formula of the compound.

Important Questions on Stoichiometry

Learn and Prepare for any exam you want !

Chemical analysis of a carbon compound gave the following percentage composition by weight of the elements present, carbon $= 10.06 %$ , hydrogen $= 0.84 %$ , chlorine $= 89.10 %$ , Calculate the empirical formula of the compound.