Classify the following as pure substances or as mixtures: air gasoline honey paint water glucose mercury oxygen salt 12 Classify the following as an element; compound, heterogeneous mixture: homogeneous mixture or & aluminum raisin bread carbon dioxide water sugar water sulfur sulfuric acid mercury steel brewed coffee spaghetti and meatballs ethanol nitrogen air gasoline guacamole
The Correct Answer and Explanation is:
Part 1: Classify as Pure Substances or Mixtures
Pure Substances:
- Water
- Glucose
- Mercury
- Oxygen
- Salt
Mixtures:
- Air
- Gasoline
- Honey
- Paint
Part 2: Classify as Element, Compound, Heterogeneous Mixture, or Homogeneous Mixture
Elements:
- Aluminum
- Sulfur
- Mercury
- Nitrogen
Compounds:
- Carbon dioxide
- Water
- Sulfuric acid
- Ethanol
Homogeneous Mixtures:
- Sugar water
- Steel
- Brewed coffee
- Air
- Gasoline
Heterogeneous Mixtures:
- Raisin bread
- Spaghetti and meatballs
- Guacamole
Explanation
To classify matter, we first determine if it is a pure substance or a mixture. A pure substance has a constant composition and consistent properties. It can be either an element or a compound. Elements are made up of only one kind of atom (e.g., nitrogen, mercury), while compounds are substances formed by chemical combinations of elements in fixed ratios (e.g., water, glucose, sulfuric acid).
Mixtures, on the other hand, consist of two or more substances that are physically combined. These do not have a fixed composition and can vary. Mixtures are further classified as either homogeneous (uniform composition throughout) or heterogeneous (non-uniform composition). For example, air is a homogeneous mixture of gases, while raisin bread is a heterogeneous mixture because its components can be seen and separated physically.
Water, glucose, oxygen, salt, and mercury are pure substances. Water and glucose are compounds, while oxygen and mercury are elements. Air, gasoline, honey, and paint are mixtures because they are made up of different substances physically blended.
In the second list, elements like aluminum, sulfur, mercury, and nitrogen consist of only one type of atom. Compounds like carbon dioxide, sulfuric acid, ethanol, and water consist of chemically bonded atoms. Sugar water, steel, brewed coffee, air, and gasoline are homogeneous mixtures because their components are evenly distributed. On the other hand, raisin bread, spaghetti and meatballs, and guacamole are heterogeneous mixtures since their components are not evenly mixed and can be visually distinguished.
