   Chapter 3, Problem 81E

Chapter
Section
Textbook Problem

Express the composition of each of the following compounds as the mass percents of its elements.a. formaldehyde, CH2Ob. glucose, C6H12O6c. acetic acid, HC2H3O2

(a)

Interpretation Introduction

Interpretation: The percentage composition (by mass) of each element in the given compounds CH2O,C6H12O6 and HC2H3O2 is to be calculated.

Concept introduction: The atomic mass is defined as the sum of number of protons and number of neutrons.

Molar mass of a substance is defined as the mass of the substance in gram of one mole of that compound.

The molar mass of any compound can be calculated by adding of atomic weight of individual atoms present in it.

To determine: The percentage composition (by mass) of each element in formaldehyde (CH2O) compound.

Explanation

The atomic weight of carbon (C) is 12.01g/mol . In the compound CH2O , only one carbon atom is present. Hence, mass of carbon in CH2O is 12.01g/mol .

The atomic weight of oxygen (O) is 15.999g/mol . In the compound CH2O , only one oxygen atom is present. Hence, mass of oxygen in CH2O is 15.999g/mol .

The atomic weight of hydrogen (H) is 1.008g/mol . In the compound CH2O , two hydrogen atoms are present. Hence, mass of hydrogen in CH2O is,

2×1.008g/mol=2.016g/mol

The molar mass is the sum of mass of individual atoms present in it.

Hence, molar mass of CH2O is calculated as,

12.01g/mol+15.999g/mol+2.016g/mol=30.025g/mol

Formula

The mass percent of element is calculated as,

Mass%ofelement=MassofelementMolarmassofcompound                                         (1)

Substitute the values of mass of carbon and molar mass of CH2O in the above equation.

Mass%ofCatom=MassofCatomMolarmassofCH2O=(12

(b)

Interpretation Introduction

Interpretation: The percentage composition (by mass) of each element in the given compounds CH2O,C6H12O6 and HC2H3O2 is to be calculated.

Concept introduction: The atomic mass is defined as the sum of number of protons and number of neutrons.

Molar mass of a substance is defined as the mass of the substance in gram of one mole of that compound.

The molar mass of any compound can be calculated by adding of atomic weight of individual atoms present in it.

To determine: The percentage composition (by mass) of each element in glucose (C6H12O6) compound.

(c)

Interpretation Introduction

Interpretation: The percentage composition (by mass) of each element in the given compounds CH2O,C6H12O6 and HC2H3O2 is to be calculated.

Concept introduction: The atomic mass is defined as the sum of number of protons and number of neutrons.

Molar mass of a substance is defined as the mass of the substance in gram of one mole of that compound.

The molar mass of any compound can be calculated by adding of atomic weight of individual atoms present in it.

To determine: The percentage composition (by mass) of each element in acetic acid (HC2H3O2) compound.

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

In many people any kind of stress can cause overeating and weight gain T F

Nutrition: Concepts and Controversies - Standalone book (MindTap Course List)

Where does most Of the translation occur in a eukaryote cell?

Introduction to General, Organic and Biochemistry

What causes an aging giant star to produce a planetary nebula?

Horizons: Exploring the Universe (MindTap Course List) 