3. Chemical Reactions

Combustion Analysis

CHEMISTRY 101:  Finding Empirical Formula Using Combustion Analysis for a Compound with C, H, O

Combustion analysis of naphthalene, a hydrocarbon used in
mothballs, produces 8.80 g CO2 and 1.44 g H2O. Calculate the
empirical formula of naphthalene.

Combustion analysis is performed on 0.50 g of a hydrocar-bon and 1.55 g of CO2, and 0.697 g of H2O are produced. The mass spectrum for the hydrocarbon is provided below. What is the molecular formula? (LO 3.12 and 3.13) <img src="https://lightcat-files.s3.amazonaws.com/problem_images/9962d9e40ceca293-1668697669260.jpg" alt="" />
(a) C5H11
(b) C8H18 
(c) C11H10
(d) C10H22

Combustion Analysis Example 1

Combustion analysis of 0.1500 g of methyl tert-butyl 
ether, an octane booster used in gasoline, gave 0.3744 g of 
CO2 and 0.1838 g of H2O. When a flask having a volume 
of 1.00 L was evacuated and then filled with methyl tertbutyl 
ether vapor at a pressure of 100.0 kPa and a temperature 
of 54.8 °C, the mass of the flask increased by 3.233 g.

(a) What is the empirical formula of methyl tert-butyl ether?

Combustion Analysis - Finding the Empirical Formula of a Compound

A hydrocarbon of unknown formula CxHy was submitted to combustion analysis with the following results. What is the empirical formula of the hydrocarbon? <img src="https://lightcat-files.s3.amazonaws.com/problem_images/74756c80b6674f4b-1668445799134.jpg" alt="" />

Combustion analysis of a hydrocarbon produces 33.01 g CO2
and 13.51 g H2O. Calculate the empirical formula of the hydrocarbon.

When hydrocarbons are burned in a limited amount of air, both CO and CO2 form. When 0.460 g of a hydrocarbon was burned in air, 0.477 g of CO, 0.749 g CO2, and 0.460 g of H2O were formed. What is the empirical formula of the compound?

The organic molecules shown here are derivatives of benzene 
in which six-membered rings are “fused” at the edges 
of the hexagons. 
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/85bc30663067d9d2-1660322637490.jpg" alt="" /> 
(b) Suppose you are given a sample 
of one of the compounds. Could combustion analysis be 
used to determine unambiguously which of the three it is?

Valproic acid, used to treat seizures and bipolar disorder, is
composed of C, H, and O. A 0.165-g sample is combusted
to produce 0.166 g of water and 0.403 g of carbon dioxide.
What is the empirical formula for valproic acid?

The equation does not contain the same number of atoms of each element with this coefficient for carbon dioxide.  Remember to take into consideration both the subscripts and coefficients.

 Add coefficients to the equation in order to ensure that the number of atoms of each element are the 

When the following equation is balanced C5H10(l) + O2(g) &#8594; CO2(g) + H2O(g)What is the coefficient for carbon dioxide?

Vanillin, the dominant flavoring in vanilla, contains C, H,
and O. When 1.05 g of this substance is completely combusted,
2.43 g of CO2 and 0.50 g of H2O are produced. What
is the empirical formula of vanillin?

(b) What products form in this 
reaction?

Tartaric acid is the white, powdery substance that coats tart candies
such as Sour Patch Kids. Combustion analysis of a 12.01-g
sample of tartaric acid—which contains only carbon, hydrogen,
and oxygen—produces 14.08 g CO2 and 4.32 g H2O.
Determine the empirical formula of tartaric acid.

(a) Combustion analysis of 150.0 mg of 1,2,3,benzenetriol, a compound composed of carbon, hydrogen, and oxy-gen, gives 64.3 mg of H2O and 314.2 mg of CO2. What is the empirical formula of 1,2,3,benzenetriol?

The combustion of 4.16 grams of a compound which contains only C,H,O and F yields 7.7 g CO2 and 2.52 g H2O. Another sample of the compound with a mass of 3.63 g is found to contain 0.58 g F. What is the empirical formula of the compound?

Combustion Analysis to determine Empirical Formulae.

(b) Nicotine, a component of tobacco, is
composed of C, H, and N. A 5.250-mg sample of nicotine was
combusted, producing 14.242 mg of CO2 and 4.083 mg of
H2O. What is the empirical formula for nicotine?

An organic compound was found to contain only C, H, and Cl.
When a 1.50-g sample of the compound was completely combusted
in air, 3.52 g of CO2 was formed. In a separate experiment,
the chlorine in a 1.00-g sample of the compound was
converted to 1.27 g of AgCl. Determine the empirical formula
of the compound.

(a) The characteristic odor of pineapple is due to ethyl butyrate,
a compound containing carbon, hydrogen, and oxygen.
Combustion of 2.78 mg of ethyl butyrate produces 6.32 mg
of CO2 and 2.58 mg of H2O. What is the empirical formula
of the compound?

The foul odor of rancid butter is due largely to butyric acid, a
compound containing carbon, hydrogen, and oxygen. Combustion
analysis of a 4.30-g sample of butyric acid produces
8.59 g CO2 and 3.52 g H2O. Determine the empirical formula of
butyric acid.

(b) Menthol, the substance we can smell
in mentholated cough drops, is composed of C, H, and O.
A 0.1005-g sample of menthol is combusted, producing
0.2829 g of CO2 and 0.1159 g of H2O. What is the empirical
formula for menthol?

(a) Combustion analysis of 50.0 mg of benzene, a commonly used solvent composed of carbon and hydrogen, gives 34.6 mg of H2O and 169.2 mg of CO2. What is the empirical formula of benzene?

Estrone, which contains only carbon, hydrogen, and oxygen, is
a female sexual hormone in the urine of pregnant women.
Combustion analysis of a 1.893-g sample of estrone produces
5.545 g of CO2 and 1.388 g H2O. The molar mass of estrone is
270.36 g/mol. Find its molecular formula.

(c) Can combustion analysis be used to determine the empirical formula of a compound containing carbon, hydrogen, oxygen, and chlorine?

Burning acetylene in oxygen can produce three different 
carbon-containing products: soot (very fine particles of 
graphite), CO(g), and CO21g2. (c) Why, when the oxygen supply 
is adequate, is CO21g2 the predominant carbon-containing 
product of the combustion of acetylene?

(a) When a compound containing C, H, and O is completely
combusted in air, what reactant besides the hydrocarbon
is involved in the reaction?

Combustion Analysis pt. 1

Combustion Analysis Example 2

Researchers obtained the following data from experiments to
find the molecular formula of benzocaine, a local anesthetic,
which contains only carbon, hydrogen, nitrogen, and oxygen.
Complete combustion of a 3.54-g sample of benzocaine with
excess O2 forms 8.49 g of CO2 and 2.14 g H2O. Another 2.35-g
sample contains 0.199 g of N. The molar mass of benzocaine is
165 g>mol. Find the molar formula of benzocaine.

(b) If the molecular weight is 326.26, what is the molecular formula?

Chem101 Combustion Analysis

(a) Combustion analysis of toluene, a common organic
solvent, gives 5.86 mg of CO2 and 1.37 mg of H2O. If the
compound contains only carbon and hydrogen, what is its
empirical formula?

(b) Menthol, the substance we can smell
in mentholated cough drops, is composed of C, H, and O.
A 0.1005-g sample of menthol is combusted, producing
0.2829 g of CO2 and 0.1159 g of H2O. What is the empirical
formula for menthol? If menthol has a molar mass of
156 g/mol, what is its molecular formula?

Compound X contains only carbon, hydrogen, nitrogen, and chlorine. When 1.00 g of X is dissolved in water and allowed to react with excess silver nitrate, AgNO3, all the chlorine in X reacts and 1.95 g of solid AgCl is formed. When 1.00 g of X undergoes complete combustion, 0.900 g of CO2 and 0.735 g of H2O are formed. What is the empirical formula of X?

(a) Polychlorinated biphenyls (PCBs) were compounds used as coolants in transformers and capacitors, but their production was banned by the U.S. Congress in 1979 because they are highly toxic and persist in the environment. When 1.0 g of a PCB containing carbon, hydrogen, and chlorine was subjected to combustion analysis, 1.617 g of CO2. and 0.138 g of H2O were produced. What is the empirical formula?

If a compound made of calcium, carbon, nitrogen undergoes combustion in oxygen to create 2.389 g CaO, 1.876 g CO2, and 3.921 g NO­2, determine its empirical formula.

Coniine, a toxic substance isolated from poison hemlock, contains only carbon, hydrogen, and nitrogen. Combus-tion analysis of a 5.024 mg sample yields 13.90 mg of CO2 and 6.048 mg of H2O. What is the empirical formula of coniine?

Valproic acid, used to treat seizures, is composed of carbon, hydrogen and oxygen. A 0.165 g sample is combusted to produce 0.166 grams of water and 0.403 grams of carbon dioxide. If the molar mass is 144 g/mol, what is the molecular formula?

(b) Nicotine, a component of tobacco, is 
composed of C, H, and N. A 5.250-mg sample of nicotine was 
combusted, producing 14.242 mg of CO2 and 4.083 mg of 
H2O. What is the empirical formula for nicotine? If nicotine 
has a molar mass of 160 { 5 g/mol, what is its molecular 
formula?

Combustion analysis of 45.62 mg of toluene, a commonly used solvent, gives 35.67 mg of H2O and 152.5 mg of CO2. What is the empirical formula of toluene?

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1. Intro to General Chemistry

2. Atoms & Elements

4. BONUS: Lab Techniques and Procedures

5. BONUS: Mathematical Operations and Functions

6. Chemical Quantities & Aqueous Reactions

7. Gases

8. Thermochemistry

9. Quantum Mechanics

10. Periodic Properties of the Elements

11. Bonding & Molecular Structure

12. Molecular Shapes & Valence Bond Theory

13. Liquids, Solids & Intermolecular Forces

14. Solutions

15. Chemical Kinetics

16. Chemical Equilibrium

17. Acid and Base Equilibrium

18. Aqueous Equilibrium

19. Chemical Thermodynamics

20. Electrochemistry

21. Nuclear Chemistry

22. Organic Chemistry

23. Chemistry of the Nonmetals

24. Transition Metals and Coordination Compounds

[BOOK CHEM] Clutch Version

Empirical Formula

The empirical formula gives the relative number of atoms.&nbsp;

Percent Yield

The Percent Yield determines how successful the product yield is in a chemical reaction.&nbsp;

Molecular Formula

The&nbsp;molecular formula gives the actual number of atoms.

Naming Ionic Compounds

An ionic compound is composed of a positive ion and a negative ion.&nbsp;

Functional Groups in Chemistry

The Functional Group is the portion of a molecule that is responsible for its chemical reactivity.&nbsp;

Naming Molecular Compounds

Molecular Compounds, also known as covalent compounds, contain only non-metals bonded together.&nbsp;

Naming Ionic Hydrates

An Ionic Hydrate is an ionic compound that is linked to at least one molecule of H2O.&nbsp;

Stoichiometry

Stoichiometry deals with the numerical relationship between compounds in a balanced chemical equation.

Writing Ionic Compounds

Determining the charges of a cation and anion are fundamental in Writing Ionic Compounds.

Polyatomic Ions

Polyatomic Ions are groups of multiple elements that possess a charge.

Balancing Chemical Equations

Balancing Chemical Equations is the first step in future chemical calculations.

Limiting Reagent

The Limiting Reagent represents the compound that is totally consumed in the reaction.&nbsp;

Under Combustion Analysis, the empirical formula of a compound is determined through a combustion reaction.&nbsp;

Mass Percent

Mass Percent is the percentage of a particular element within a compound.&nbsp;

Combustion Apparatus

A Combustion Apparatus vaporizes a sample into gases to later determine its formula.

Naming Acids

Acids, for the most part, are covalent compounds that begin with a hydrogen.&nbsp;