Problem 67 - Chemistry Matter and Change

Question

Name the elements contained in the following compounds. \(\begin{array}{ll}{\text { a. sodium chloride (NaCl) }} & {\text { c. ethanol }\left(C_{2} H_{6} O\right)} \\ {\text { b. ammonia ( } NH_{3} )} & {\text { d. bromine }\left(Br_{2}\right)}\end{array}\)

Step-by-Step Solution

Answer

The elements contained in the given compounds are: a. Sodium chloride (NaCl): Sodium and Chlorine b. Ammonia (NH3): Nitrogen and Hydrogen c. Ethanol (C2H6O): Carbon, Hydrogen, and Oxygen d. Bromine (Br2): Bromine

Step 1: a. Naming elements in sodium chloride (NaCl)

Sodium chloride (NaCl) is composed of two elements: sodium (Na) and chlorine (Cl). So, the elements present in this compound are Sodium and Chlorine.

Step 2: b. Naming elements in ammonia (NH3)

Ammonia (NH3) is composed of two elements: nitrogen (N) and hydrogen (H). So, the elements present in this compound are Nitrogen and Hydrogen.

Step 3: c. Naming elements in ethanol (C2H6O)

Ethanol (C2H6O) is composed of three elements: carbon (C), hydrogen (H), and oxygen (O). So, the elements present in this compound are Carbon, Hydrogen, and Oxygen.

Step 4: d. Naming elements in bromine (Br2)

Bromine (Br2) is composed of only one element: bromine (Br). So, the only element present in this compound is Bromine.

Key Concepts

Chemical Compounds

Chemical compounds are substances composed of two or more different elements that are chemically bonded together. These compounds are formed through chemical reactions between elements.

• Compounds have unique properties that are distinct from the individual atoms that comprise them. For instance, water ( \( \text{H}_2\text{O} \) ) has properties entirely different from hydrogen and oxygen gases.
• The chemical formula represents the types and numbers of atoms in a compound. For example, in sodium chloride ( \( \text{NaCl} \) ), 'Na' stands for sodium, and 'Cl' stands for chlorine.
• There are various types of chemical compounds, such as ionic compounds (like sodium chloride), molecular compounds (like water and ammonia), and more complex structures such as proteins.

Understanding the composition of chemical compounds is crucial to studying reactions and properties in chemistry.

Periodic Table

The periodic table is a comprehensive chart that displays all known chemical elements organized by increasing atomic number. Each element is represented by a unique one or two-letter symbol.

• The table is divided into rows called periods and columns known as groups or families. Elements in the same group have similar chemical properties.
• Metals are typically found on the left and center of the table, non-metals are on the right, and metalloids form a zigzag line between them.
• Each element's position in the table helps predict its behavior in chemical reactions due to similarities in electron configurations with other elements in the same group.

The periodic table is a powerful tool for understanding the relationships between elements, predicting reactions, and aiding in the identification of chemical compounds.

Element Identification

Element identification in compounds involves recognizing the symbols and formulas that represent elements. Each element's symbol is derived from its English or Latin name and is a critical component of chemical literacy.

• To identify elements in a compound, look at its chemical formula. The formula tells what elements are present and their relative quantities.
• For example, in ethanol ( \( \text{C}_2\text{H}_6\text{O} \) ), the formula reveals the presence of carbon (C), hydrogen (H), and oxygen (O).
• Understanding element symbols and formulas is essential for naming compounds and balancing chemical equations.

This process of element identification is fundamental to mastering chemistry and is a skill that becomes easier with practice and familiarity with the periodic table.