Question

Identify the solute and solvent in this solution containing sodium chloride and water. Explain your answer.

Short answer

In the given solution, water is the solvent and sodium chloride is the solute. Water, the substance in larger amount and the one doing the dissolving, is the solvent, while sodium chloride, the substance that gets dissolved, is the solute.

Step-by-step solution

Understanding the Concepts of Solute and Solvent

A solute is defined as the substance that is dissolved in a solution. On the other hand, a solvent is the substance in a solution that does the dissolving. It's usually present in a larger quantity.

Identifying the Solute and Solvent

In the given solution, sodium chloride (NaCl) is dissolved in water. Hence, sodium chloride is the solute, as it is the substance that has been dissolved. Water is the solvent, because it is the substance that has done the dissolving.

Explanation

In any solution, the solvent is the substance that is usually present in the greatest quantity. Water is often called the 'universal solvent' because it can dissolve so many different substances. In this case, water has taken the sodium chloride (salt) and evenly distributed it within itself, making water the solvent and sodium chloride the solute.

Key concepts

Solution Chemistry

In the world of chemistry, a solution is a homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance that is dissolved in another substance, known as the solvent. The solution has the same physical state as the solvent. For example, when you dissolve table sugar in water, the sugar is the solute, and the water is the solvent. A critical aspect of solution chemistry is the concentration of the solute. The amount of solute in a given amount of solvent or solution is expressed as concentration. There are various ways to express concentration such as molarity, molality, and parts per million (ppm).

Solubility, another key term in solution chemistry, refers to how well a substance can be dissolved. Temperature and pressure play significant roles in determining the solubility of a substance. For instance, increasing the temperature generally increases solubility for solids in liquids but has varying effects for gases.

Dissolving Process

The dissolving process is a physical change where particles of a solute integrate into a solvent, forming a solution. At the molecular level, this process begins when the solvent particles surround the solute particles, which can be observed when salt is mixed into water. Attractions between solute and solvent particles must overcome the forces holding the solute particles together. This is why ionic compounds like sodium chloride dissolve readily in water; the positively charged and negatively charged ions are attracted to the polar water molecules.

During the dissolving process, three main interactions occur: solute-solute interaction, solvent-solvent interaction, and solute-solvent interaction. The ease at which the solute dissolves, known as solubility, depends on the balance between these forces and is a fundamental aspect of the substance's nature and the conditions of the solution.

Properties of Water

Water is often referred to as the 'universal solvent' due to its remarkable ability to dissolve many substances, which is primarily attributed to its polar nature and hydrogen bonding. A water molecule consists of two hydrogen atoms bonded to an oxygen atom. The electrons in the water molecule are not shared equally, making one end of the molecule slightly positive and the other end slightly negative. This polarity allows water to form hydrogen bonds with other polar molecules and ions.

The properties of water make it an excellent medium for the occurrence of biological and chemical processes. It has a high specific heat, moderating temperatures within organisms and environments. Its solid form, ice, is less dense than its liquid form, which allows ice to float, insulating aquatic life in winter. Water’s solvent properties are vital for processes such as transporting nutrients and waste within living organisms and facilitating chemical reactions in cells.