Chapter 2, Problem 2.12P

(a)

Interpretation Introduction

Interpretation: Whether percent by mass of each element in a compound depends on the amount of compound or not should be determined.

Concept introduction:Elements consist of a single type of atom of fixed atomic number. They are represented by the symbol of that atom. Elements cannot be dissociated by simple chemical methods. Elements can be classified broadly into two groups Atomic elements and molecular elements.Examples of atomic elements are iron $\left(\text{Fe}\right)$ , copper $\left(\text{Cu}\right)$ , gold $\left(\text{Au}\right)$ , and examples of molecular elements are oxygen $\left({\text{O}}_{\text{2}}\right)$ , octasulfur $\left({\text{S}}_{\text{8}}\right)$ .

Compounds are substances that are composed of at least two or more than two elements bound chemically in fixed proportions. They are represented by their chemical compositions. Compounds can be fragmented into its constituents by chemical methods.Examples of compounds are water $\left({\text{H}}_{\text{2}}\text{O}\right)$ , common salt $\left(\text{NaCl}\right)$ and carbon dioxide $\left({\text{CO}}_{\text{2}}\right)$ .

(b)

Interpretation Introduction

Interpretation:Whether mass of each element in a compound depends on the amount of compound is determined or not should be determined.

Concept introduction:Elements consist of a single type of atom of fixed atomic number. They are represented by the symbol of that atom. Elements cannot be dissociated by simple chemical methods. Elements can be classified broadly into two groups Atomic elements and molecular elements.Examples of atomic elements are iron $\left(\text{Fe}\right)$ , copper $\left(\text{Cu}\right)$ , gold $\left(\text{Au}\right)$ , and examples of molecular elements are oxygen $\left({\text{O}}_{\text{2}}\right)$ , octasulfur $\left({\text{S}}_{\text{8}}\right)$ .

Compounds are substances that are composed of at least two or more than two elements bound chemically in fixed proportions. They are represented by their chemical compositions. Compounds can be fragmented into its constituents by chemical methods. Examples of compounds are water $\left({\text{H}}_{\text{2}}\text{O}\right)$ , common salt $\left(\text{NaCl}\right)$ and carbon dioxide $\left({\text{CO}}_{\text{2}}\right)$ .