1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
FinnZ [79.3K]
3 years ago
14

Combustion analysis of a 13.42-g sample of the unknown organic compound (which contains only carbon, hydrogen, and oxygen) produ

ced 39.61 g CO2 and 9.01 g H2O. The molar mass of equilin is 268.34 g/mol. Find its molecular formula.
Chemistry
1 answer:
kirza4 [7]3 years ago
3 0

<u>Answer:</u> The molecular formula for the given organic compound is C_{18}H_{20}O_2

<u>Explanation:</u>

The chemical equation for the combustion of hydrocarbon having carbon, hydrogen and oxygen follows:

C_xH_yO_z+O_2\rightarrow CO_2+H_2O

where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and oxygen respectively.

We are given:

Mass of CO_2=39.61g

Mass of H_2O=9.01g

We know that:

Molar mass of carbon dioxide = 44 g/mol

Molar mass of water = 18 g/mol

<u>For calculating the mass of carbon:</u>

In 44 g of carbon dioxide, 12 g of carbon is contained.

So, in 39.61 g of carbon dioxide, \frac{12}{44}\times 39.61=10.80g of carbon will be contained.

<u>For calculating the mass of hydrogen:</u>

In 18 g of water, 2 g of hydrogen is contained.

So, in 9.01 g of water, \frac{2}{18}\times 9.01=1.00g of hydrogen will be contained.

Mass of oxygen in the compound = (13.42) - (10.80 + 1.00) = 1.62 g

To formulate the empirical formula, we need to follow some steps:

  • <u>Step 1:</u> Converting the given masses into moles.

Moles of Carbon = \frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{10.80g}{12g/mole}=0.9moles

Moles of Hydrogen = \frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{1g}{1g/mole}=1moles

Moles of Oxygen = \frac{\text{Given mass of oxygen}}{\text{Molar mass of oxygen}}=\frac{1.62g}{16g/mole}=0.10moles

  • <u>Step 2:</u> Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 0.10 moles.

For Carbon = \frac{0.9}{0.10}=9

For Hydrogen = \frac{1}{0.10}=10

For Oxygen = \frac{0.10}{0.10}=1

  • <u>Step 3:</u> Taking the mole ratio as their subscripts.

The ratio of C : H : O = 9 : 10 : 1

Hence, the empirical formula for the given compound is C_9H_{10}O

For determining the molecular formula, we need to determine the valency which is multiplied by each element to get the molecular formula.

The equation used to calculate the valency is :

n=\frac{\text{Molecular mass}}{\text{Empirical mass}}

We are given:

Mass of molecular formula = 268.34 g/mol

Mass of empirical formula = 134 g/mol

Putting values in above equation, we get:

n=\frac{268.34g/mol}{134g/mol}=2

Multiplying this valency by the subscript of every element of empirical formula, we get:

C_{(9\times 2)}H_{(10\times 2)}O_{(1\times 2)}=C_{18}H_{20}O_2

Thus, the molecular formula for the given organic compound is C_{18}H_{20}O_2.

You might be interested in
A student is asked to convert measurements from liters to milliliters and from milliliters to liters. His answers are shown in b
kirza4 [7]
The answer is 3.6L=360mL
5 0
3 years ago
Read 2 more answers
Question 34 (1 point)
Grace [21]

Answer:

8.33 atm

Explanation:

Xe is   5  out of (4+5)   or   5 / 9 ths of the gas present

  5/9  * 15 atm = 8.33 atm

4 0
1 year ago
A solid that forms and separates from a liquid mixture is a.......
inna [77]

A solid that forms and separates from a liquid mixture is a chemical change.

4 0
3 years ago
The earth was created about_____ years ago. 15,000 20,000 6,000 3,000
Sphinxa [80]
It was created about 6,000 years ago
5 0
3 years ago
Which of the following food proteins has the best assortment of essential amino acids for the human body?​
Katen [24]
The answer to your question is an Egg

7 0
3 years ago
Other questions:
  • 1. Define the term disproportionation reaction. 2. Write the balanced equation for the conversion of 4-chlorobezaldehye into 4-c
    11·1 answer
  • A medical lab is testing a new anticancer drug on cancer cells. The drug stock solution concentration is 1.5×10−9m, and 1.00 ml
    9·2 answers
  • An unknown element is shiny and is found to be a good conductor of electricity, what other properties would you predict for it
    9·1 answer
  • What keeps an electron in motion around the nucleus to which it is attracted?
    14·1 answer
  • What is the IUPAC name of the following compound?
    10·1 answer
  • Assuming all other variables are constant, if the pressure of a gas is increased from 2. atm to 6 atm the volume would change fr
    6·1 answer
  • A. 24.5 g of ammonia NH3 = how many moles of ammonia?
    7·1 answer
  • Hey y’all, I’m growing a plant for science class but I need some questions about the plant, can someone please give me atleast 3
    14·1 answer
  • Electrical energy is transformed into many energy forms and is used to power most of the household appliances we used every day.
    9·1 answer
  • Which of the following compounds has the general formula X3Y2?Which of the following compounds has the general formula X3Y2?
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!