Question

Provide the formula for each of the following binary acids: (a) hydrosulfuric acid (b) hydroselenic acid

Short answer

(a) \(\text{H}_2\text{S}\); (b) \(\text{H}_2\text{Se}\).

Step-by-step solution

Understand what a binary acid is

Binary acids are acids that consist of hydrogen and one other nonmetal element. They typically have the prefix 'hydro-' and the suffix '-ic acid' in their names.

Identify the components of each acid

For both hydrosulfuric acid and hydroselenic acid, the acids consist of hydrogen and another nonmetal element (sulfur and selenium, respectively).

Determine the chemical formula for hydrosulfuric acid

Hydrosulfuric acid is formed from hydrogen and sulfur. The common formula for this acid is \(\text{H}_2\text{S}\), where two hydrogen atoms combine with one sulfur atom to form hydrogen sulfide.

Determine the chemical formula for hydroselenic acid

Hydroselenic acid is formed from hydrogen and selenium. The formula is \(\text{H}_2\text{Se}\), where two hydrogen atoms combine with one selenium atom to form hydrogen selenide.

Key concepts

Chemical Formula

A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. It indicates the types and numbers of atoms involved in a compound. In binary acids, the chemical formula is particularly simple because it consists only of hydrogen and one other nonmetal.

Binary acids are characterized by having hydrogen as their first element. The nonmetal part will determine both the suffix and the prefix of the compound's name. This simple structure allows for straightforward formula writing.

• The prefix 'hydro-' refers to the presence of hydrogen.
• The suffix '-ic acid' indicates that the compound is an acid.

For instance, in the case of hydrosulfuric acid and hydroselenic acid, the chemical formulae are based on combining hydrogen with sulfur and selenium, respectively. This makes it easy to understand and remember how to write such acid formulas.

Hydrosulfuric Acid

Hydrosulfuric acid is a common example of a binary acid, consisting of hydrogen and sulfur. The chemical formula for hydrosulfuric acid is \[ \text{H}_2\text{S} \] where two hydrogen atoms bond with a single sulfur atom. This structure is also known as hydrogen sulfide, and it is important in various industrial processes.

Hydrosulfuric acid, in its aqueous form, is less commonly encountered than hydrogen sulfide in its gaseous state. Nonetheless, understanding its composition helps when dealing with its chemical behavior:

• Hydrosulfuric acid is known for its distinct "rotten egg" smell.
• It is a weak acid, balancing the number of hydrogen and sulfur atoms appropriately to form \( \text{H}_2 \text{S} \).
• Its solutions become corrosive at certain concentrations, making it an important chemical in safety considerations.

Hydroselenic Acid

Hydroselenic acid is another exemplary binary acid composed of hydrogen and selenium. Its chemical formula is \[ \text{H}_2\text{Se} \] , indicating that two hydrogen atoms form a bond with one selenium atom. This structure forms the compound known as hydrogen selenide.

Hydroselenic acid is noted for different characteristics and uses compared to hydrosulfuric acid:

• Hydroselenic acid is less commonly encountered than hydrogen selenide in nature.
• This compound is toxic and must be handled with care. It is also corrosive, especially in its concentrated forms.
• Despite its rare occurrence, it plays a role in the synthesis of organic selenium compounds, showcasing its importance in organic chemistry.

Understanding the formula and properties of hydroselenic acid aids in its safe utilization and management in laboratory settings.