Question

If the oxide of an element dissolves in water to give an acidic solution, is the element more likely to be a metal or a nonmetal?

Short answer

The element is more likely to be a nonmetal since nonmetallic oxides generally dissolve in water to form acidic solutions.

Step-by-step solution

Determine the Nature of Oxides

Firstly, understand that oxides are compounds formed when an element reacts with oxygen. Depending on the element's nature, the oxides can either be acidic, basic, or amphoteric. Acidic oxides generally form when nonmetals react with oxygen, while basic oxides form from the reaction of metals with oxygen.

Assess the Behavior in Water

In the given exercise, the oxide dissolves in water to form an acidic solution. This behavior is characteristic of acidic oxides. When acidic oxides dissolve in water, they form acids.

Identify the Type of Element

Since the oxide forms an acid when dissolved in water, it suggests that the oxide is acidic. Acidic oxides are typically formed from nonmetals. Therefore, the element in question is more likely to be a nonmetal.

Key concepts

Nonmetal Oxides

Oxides are chemical compounds that contain at least one oxygen atom and one other element. Nonmetal oxides are a specific type of oxide where the other element is a nonmetal. These oxides typically exhibit certain characteristics that differentiate them from oxides that contain metals.

Common examples of nonmetal oxides include carbon dioxide \( CO_2 \), sulfur dioxide \( SO_2\), and nitrogen dioxide \( NO_2 \). These compounds play crucial roles in various chemical processes, both natural and industrial. For instance, carbon dioxide is involved in the greenhouse effect and cellular respiration, while sulfur dioxide can lead to acid rain when released into the atmosphere.

Nonmetal oxides are often formed through reactions between nonmetals and oxygen occurring during combustion or corrosion processes. In the lab, they can be prepared by direct reactions at high temperatures or by oxidizing nonmetals with oxidizing agents. A characteristic trait of nonmetal oxides is their tendency to form acidic solutions when they react with water, which is essential in understanding their role in environmental chemistry.

Reaction of Oxides with Water

The reaction of oxides with water is fundamental in predicting the pH of the resulting solution and understanding the oxides' behavior in the environment. When oxides react with water, they can form either acidic, basic, or neutral solutions.

In the case of nonmetal oxides, the reaction typically results in the formation of an acid. For instance, carbon dioxide reacts with water to form carbonic acid \(H_2CO_3\):\[ CO_2 + H_2O \rightarrow H_2CO_3 \]
Similarly, sulfur dioxide in water forms sulfurous acid \(H_2SO_3\):\[ SO_2 + H_2O \rightarrow H_2SO_3 \]
This acid-forming reaction of nonmetal oxides with water is a vital process in nature. It has implications for acid rain, where oxides from industrial emissions dissolve in raindrops to create acidic precipitation damaging to many ecosystems.

Properties of Acidic Oxides

Understanding the properties of acidic oxides is critical in predicting how they will interact with other substances and in their identification. Acidic oxides, formed by nonmetals, have some distinctive properties that can be observed through their reactions with bases and water.

Firstly, acidic oxides are soluble in water, leading to the formation of acids, a process that typifies their corrosive nature. The resulting solutions have a low pH, indicating their acidity. For example, the dissolution of sulfur dioxide in water forms a solution with a pH less than 7, indicative of an acid.

Additionally, acidic oxides react with bases to form salts and water in a neutralization reaction. For example: \[ SO_2 + 2NaOH \rightarrow Na_2SO_3 + H_2O \]
Here, sulfur dioxide reacts with sodium hydroxide to form sodium sulfite and water.

These properties of acidic oxides reflect their nonmetallic origin and are significant for various environmental and industrial processes. They are central to topics like atmospheric chemistry, where understanding the behavior of such compounds is essential to tackling issues like pollution and climate change.