Question

Give the IUPAC systematic name for each of the following binary acids: (a) \(\operatorname{HBr}(a q)\) (b) \(\mathrm{HI}(a q)\)

Short answer

(a) Hydrobromic acid, (b) Hydroiodic acid.

Step-by-step solution

Understand Binary Acid Naming Conventions

Binary acids are composed of hydrogen and one other nonmetal element. When naming these acids, use the prefix "hydro-" followed by the root of the nonmetal's name and the suffix "-ic," then add the word "acid." This naming convention applies only when the acid is in an aqueous solution, as denoted by \((aq)\).

Identify the Nonmetal in Each Acid

For each given substance, identify the nonmetal that is bonded with hydrogen. (a) In \(\mathrm{HBr}(aq)\), the nonmetal partner is bromine. (b) In \(\mathrm{HI}(aq)\), the nonmetal partner is iodine.

Apply the Naming Convention to HBr

Following the binary acid naming rule, start with "hydro-" then use the root name of bromine, which is "brom-", add the suffix "-ic," and conclude with the word "acid." The systematic name for \(\mathrm{HBr}(aq)\) is "hydrobromic acid."

Apply the Naming Convention to HI

Using the naming rule, begin with "hydro-", then the root of iodine, which is "iod-", followed by the suffix "-ic," and the word "acid." Thus, the systematic name for \(\mathrm{HI}(aq)\) is "hydroiodic acid."

Key concepts

Binary Acids

Binary acids are a specific category of acids that consist of only hydrogen and one other element, which must be a nonmetal. These acids are typically found in aqueous solutions, meaning they are dissolved in water.
For instance, - iIn the formula - iat - iy acids, the notation should have the \(aq\) symbol to signify that the substance is in an aqueous state.
When these acids are dissolved in water, they exhibit their acidic properties, such as turning blue litmus paper red and reacting with bases to form salts.

Naming Conventions

Understanding the naming conventions for binary acids is essential to identifying them correctly. The rules are straightforward and include only a few key steps.
- Use the prefix "hydro-" to signal that the acid starts with hydrogen. - Find the root of the nonmetal element's name.- Add the suffix "-ic" to the root of the nonmetal's name.- Lastly, append the word "acid" to complete the name.
For example, in the binary acid \(HBr(aq)\), the nonmetal is bromine. Applying the convention, we derive its IUPAC name: "hydrobromic acid." Similarly, for \(HI(aq)\), where the nonmetal is iodine, the name becomes "hydroiodic acid." These conventions are important for chemists to communicate effectively about compounds.

Systematic Names for Acids

Systematic names for acids offer a way for scientists to unambiguously identify chemical substances. These names are dictated by IUPAC guidelines, which aim to provide a global standard for chemical nomenclature.
In the case of binary acids, the systematic approach aids in ensuring that anyone with a chemistry background can quickly understand the composition and nature of the acid just by hearing its name.

• The prefix "hydro-" indicates the hydrogen ion.
• The root derived from the nonmetal's name provides information about the identity of the nonmetal present.
• The suffix "-ic" signifies that the compound is an acid.

This systematic naming is crucial because it prevents misunderstandings and errors in the field of chemistry, especially when communicating across different languages and regions. By learning and applying these naming conventions, students and practitioners assure accurate and efficient science communication.