Problem 69 - Chemistry: The Central Science

Question

Give the name or chemical formula, as appropriate, for each of the following acids: (a) \(\mathrm{HBrO}_{3}\), (b) \(\mathrm{HBr}\), (c) \(\mathrm{H}_{3} \mathrm{PO}_{4}\), (d) hypochlorous acid, \((\mathrm{e})\) iodic acid, \((\mathrm{f})\) sulfurous acid.

Step-by-Step Solution

Answer

The short versions of the answers are: (a) Bromic acid (b) Hydrobromic acid (c) Phosphoric acid (d) \(HClO\) (e) \(HIO_3\) (f) \(H_2SO_3\)

Step 1: Recognize the type of acid

HBrO3 is an oxyacid, meaning that it contains hydrogen, oxygen, and another element. In this case, the other element is bromine (Br).

Step 2: Identify the prefix and suffix

Since it's an oxyacid, we need to identify the appropriate prefix and suffix. The prefix "per-" is added if there's one more oxygen atom than the oxyacid with the "-ate" suffix, and in this case, the "-ate" suffix is used.

Step 3: Name the acid

Combining the information from the previous steps, the name of this acid is: bromic acid #b) Naming HBr#

Step 4: Recognize the type of acid

HBr is a binary acid, meaning that it contains hydrogen and only one other element. In this case, the other element is bromine (Br).

Step 5: Identify the prefix and suffix

Since it's a binary acid, we use the prefix "hydro-" and the suffix "-ic."

Step 6: Name the acid

Combining the prefix and suffix, the name of this acid is: hydrobromic acid #c) Naming H3PO4#

Step 7: Recognize the type of acid

H3PO4 is an oxyacid, meaning that it contains hydrogen, oxygen, and another element. In this case, the other element is phosphorus (P).

Step 8: Identify the prefix and suffix

In this case, there is no need for a prefix, and we use the "-ic" suffix since the oxyacid has the maximum number of oxygens associated with phosphorus.

Step 9: Name the acid

Combining the information from previous steps, the name of this acid is: phosphoric acid #d) Chemical formula of hypochlorous acid#

Step 10: Recognize the type of acid

Hypochlorous acid is an oxyacid with the name indicating the other element (chlorine) and the prefix "hypo-" indicating one less oxygen atom than the "-ous" acid.

Step 11: Determine the chemical formula

The chemical formula for the "-ous" acid, chlorous acid, is HClO2. Therefore, hypochlorous acid has one less oxygen atom: HClO #e) Chemical formula of iodic acid#

Step 12: Recognize the type of acid

Iodic acid is an oxyacid with the name indicating the other element (iodine) and the "-ic" suffix implying the maximum number of oxygens that the acid can have.

Step 13: Determine the chemical formula

The chemical formula for iodic acid is: HIO3 #f) Chemical formula of sulfurous acid#

Step 14: Recognize the type of acid

Sulfurous acid is an oxyacid with the name indicating the other element (sulfur) and the "-ous" suffix implying one less oxygen atom than the "-ic" acid.

Step 15: Determine the chemical formula

The chemical formula for the "-ic" acid, sulfuric acid, is H2SO4. Therefore, sulfurous acid has one less oxygen atom: H2SO3

Key Concepts

Oxyacids

Oxyacids are a group of acids that consist of hydrogen, oxygen, and another element, typically a non-metal. These acids are named based on the central atom, and their nomenclature shifts according to the oxygen content in the molecule.
An important aspect of naming oxyacids is recognizing the suffixes and prefixes. The suffix "-ic" is used when the acid contains the most oxygen atoms typically associated with the central element. On the other hand, "-ous" suggests one fewer oxygen atom. Moreover, the prefix "per-" indicates one more oxygen than the "-ic" acid, while "hypo-" indicates one less oxygen atom than the "-ous" acid.

• An example is HBrO₃, known as bromic acid, where bromine is the central element.
• An acid with the formula HClO, called hypochlorous acid, features chlorine with fewer oxygens than in chloric acid, thus the use of "hypo-" and "-ous."

By learning the naming rules and formula derivations, understanding oxyacids becomes easier.

Binary Acids

Binary acids are made up of hydrogen and one other non-metal element. The nomenclature for these acids follows a straightforward pattern different from that of oxyacids.
When naming binary acids, start with the prefix "hydro-" to signify the hydrogen component. Then, use the root of the non-metal's name followed by the suffix "-ic." Finally, the term "acid" is added to complete the name.

• For instance, HBr is called hydrobromic acid, where bromine (Br) is the non-metal element.

This distinct naming style helps easily differentiate binary acids from oxyacids. Understanding the constituents and the naming rules is key to mastering the concept of binary acids.

Chemical Formulas

Creating accurate chemical formulas for acids involves understanding the composition and structure of the acid.
To derive the formula, first identify the type of acid—binary or oxyacid—and apply the specific rules.

• For binary acids like hydrobromic acid, note the presence of hydrogen and the single non-metal, resulting in the formula HBr.
• For oxyacids, the number of oxygen atoms is crucial. phophoric acid (H₃PO₄) illustrates the typical maximum oxygen count for phosphorus.

Constructing chemical formulas correctly reflects the compound’s nature and provides insight into its chemical behavior.

Acid Naming Rules

The naming of acids is governed by a set of consistent rules that consider the elements and the type of acid.
These naming conventions help in identifying the structure and composition of acids easily and accurately.

• For oxyacids, recognize whether the acid contains the maximum oxygen atoms ("-ic") or fewer ("-ous"). Prefixes "hypo-" and "per-" are added for variations in oxygen content.
• Binary acids strictly follow the "hydro-" and "-ic" suffix rules.

Learning and applying these rules consistently will make acid nomenclature straightforward and help you convey chemical information reliably. By mastering these naming rules, students can greatly improve their understanding and ability to work with different acids in chemistry.