Question

Classify the following as mixtures or as pure substances. a. a multivitamin tablet b. the blue liquid in your car's windshield washer c. a Spanish omelet d. distilled water.

Short answer

a. Mixture b. Mixture c. Mixture d. Pure Substance

Step-by-step solution

Item a: A multivitamin tablet

A multivitamin tablet consists of various vitamins, minerals, and other ingredients that are combined together to create the tablet. Thus, it is a combination of multiple substances and can be classified as a mixture.

Item b: The blue liquid in your car's windshield washer

The blue liquid in a car's windshield washer is a mixture of water, solvents, detergents, and numerous additives to provide cleaning and antifreeze properties. This indicates that it is a blend of different substances and can be classified as a mixture.

Item c: A Spanish omelet

A Spanish omelet is made up of several ingredients such as eggs, potatoes, onions, and other possible seasonings. As it is a composition of multiple ingredients that are not chemically combined, it can be classified as a mixture.

Item d: Distilled water

Distilled water is produced by boiling water and collecting the steam, which is then condensed back into water, effectively purifying it. Although distilled water may not be 100% pure, it is the closest of the given options to being a pure substance, specifically to its high concentration of water (H2O) composed of hydrogen and oxygen elements chemically combined. Thus, it can be classified as a pure substance.

Key concepts

Classification Of Matter

Matter can be classified into two main categories: pure substances and mixtures. Classification helps us understand the composition and properties of different substances that make up the world around us.

• Pure substances have a consistent composition and fixed properties. They include elements and compounds formed by chemical bonding of two or more elements.
• Mixtures consist of two or more substances physically combined, and their properties can vary depending on the percentage of their components. Mixtures can be either homogeneous or heterogeneous.

Understanding the classification of matter is crucial for identifying substances in various scientific and practical contexts. It helps in analyzing how substances can be separated or used based on their classification.

Mixture

Mixtures are physical combinations of two or more substances where each substance retains its individual characteristics. They are classified as either homogeneous or heterogeneous, depending on the uniformity of their composition.

• Homogeneous mixtures are uniform throughout, meaning the composition is consistent at any point in the mixture, like salt water. They are also known as solutions.
• Heterogeneous mixtures have a non-uniform composition with distinct phases or parts, such as a salad or a Spanish omelet.

A multivitamin tablet, the blue liquid in car windshield washers, and a Spanish omelet are all examples of mixtures. In these mixtures, the different components are physically combined, and no chemical reactions occur between them.

Pure Substance

Pure substances consist of a single type of particle, which means their composition is the same throughout. They are categorized into elements and compounds:

• Elements are pure substances consisting only of one type of atom. Examples are oxygen, gold, and helium.
• Compounds are substances formed from two or more elements chemically bonded together in a fixed ratio. Water (H₂O) is a classic example of a compound.

Distilled water is considered a pure substance because it primarily consists of water molecules, which are chemically bonded hydrogen and oxygen atoms. This consistency in composition distinguishes pure substances from mixtures.