Problem 95 - Chemistry Matter and Change

Question

Write the formula for each molecule. \(\begin{array}{ll}{\text { a. sulfur difluoride }} & {\text { c. carbon tetrafluoride }} \\ {\mathbf{b} \text { . silicon tetrachloride }} & {\text { d. sulfurous acid }}\end{array}\)

Step-by-Step Solution

Answer

The formulas for each molecule are: a. Sulfur difluoride: \( SF_2 \) b. Silicon tetrachloride: \( SiCl_4 \) c. Carbon tetrafluoride: \( CF_4 \) d. Sulfurous acid: \( H_2SO_3 \)

Step 1: a. Sulfur difluoride

To write the formula for sulfur difluoride, we first find the chemical symbols for sulfur and fluorine, which are S and F, respectively. The prefix "di" in difluoride indicates that there are two fluorine atoms. Therefore, the formula is: \( SF_2 \).

Step 2: b. Silicon tetrachloride

To write the formula for silicon tetrachloride, we find the chemical symbols for silicon and chlorine, which are Si and Cl, respectively. The prefix "tetra" in tetrachloride indicates that there are four chlorine atoms. Therefore, the formula is: \( SiCl_4 \).

Step 3: c. Carbon tetrafluoride

To write the formula for carbon tetrafluoride, we find the chemical symbols for carbon and fluorine, which are C and F, respectively. The prefix "tetra" in tetrafluoride indicates that there are four fluorine atoms. Therefore, the formula is: \( CF_4 \).

Step 4: d. Sulfurous acid

To write the formula for sulfurous acid, we first recognize that this is an acid and will have a hydrogen component. The chemical symbol for hydrogen is H. Second, we analyze the name "sulfurous" which indicates sulfur and oxygen atoms. Sulfur's chemical symbol is S, and oxygen's chemical symbol is O. Sulfurous acid has the general formula of \( H_2SO_3 \).

Key Concepts

Nomenclature

The nomenclature of chemical compounds helps scientists communicate accurately about chemical substances. In chemistry, the name of a compound tells us something about its composition. For example, sulfur difluoride is made of sulfur (S) and two fluorine (F) atoms. This is indicated by the prefix "di," meaning two.
Similarly, carbon tetrafluoride includes carbon (C) and four fluorine atoms; "tetra" implies four. Understanding these prefixes can help anyone deduce the molecular structure of a compound from its name. For acids like sulfurous acid, the name hints at its content as well. The ending "-ous" traditionally suggests fewer oxygen atoms compared to "-ic" endings, commonly used in chemistry nomenclature.

Molecular Composition

Molecular composition refers to the elements and their quantities that comprise a molecule. Each different type of atom within a molecule contributes to the overall structure and properties of the compound.
In sulfur difluoride (\(SF_2\)), the molecule is made up of one sulfur atom bonded with two fluorine atoms. In silicon tetrachloride (\(SiCl_4\)), three chlorine atoms surround a central silicon atom. Understanding this composition helps in imagining the spatial arrangement and potential reactions of the molecule.
Knowing the composition is crucial because it influences properties like melting points, boiling points, and solubility. Such knowledge is also fundamental in predicting the behavior of chemicals in reactions.

Chemical Symbols

Chemical symbols are abbreviations derived mostly from the English or Latin name of an element. They provide a universal shorthand to depict the various elements present in a given compound.
For instance, S represents sulfur, Cl represents chlorine, and O represents oxygen. This system of symbols makes it easier for chemists around the world to identify elements and compounds without ambiguities.
When writing chemical formulas, like \(CF_4\) for carbon tetrafluoride, these symbols are combined with numerical subscripts. These indicate the number of atoms of each element in the molecule. It's a concise and universally understood method to describe molecular makeup. Understanding this language allows clear and consistent communication in scientific contexts.