Classify each substance as a pure substance or a mixture. If it is a pure substance, classify it as an element or a compound. if it is a mixture, classify it as homogeneous or heterogeneous.
A. wine
C. iron
B. beef stew
D. carbon monoxide
The Correct Answer and Explanation is:
To classify the substances provided, we need to understand the definitions of pure substances and mixtures. A pure substance is a material with a constant composition and consistent properties throughout, which can be either an element (a substance that cannot be broken down into simpler substances) or a compound (a substance formed when two or more elements chemically combine in fixed ratios). A mixture, on the other hand, is a combination of two or more pure substances that retain their individual properties. Mixtures can be homogeneous (uniform composition throughout) or heterogeneous (composition that varies from one region to another).
Classification of Each Substance:
a. Wine: Mixture, homogeneous
b. Beef stew: Mixture, heterogeneous
c. Iron: Pure substance, element
d. Carbon monoxide: Pure substance, compound
Explanation:
- Wine is classified as a homogeneous mixture. It consists mainly of water, alcohol, and various organic compounds, but it appears uniform throughout. The individual components (like ethanol and water) are not visibly distinguishable from one another, which is characteristic of a homogeneous mixture. The properties of wine, such as flavor and color, are influenced by the various compounds dissolved in the liquid.
- Beef stew is classified as a heterogeneous mixture. This is because it consists of various ingredients such as meat, vegetables, and broth that are not uniformly distributed. When you look at beef stew, you can see distinct pieces of meat, carrots, potatoes, and other ingredients, illustrating the characteristic of a heterogeneous mixture where different components can be identified and separated physically.
- Iron is classified as a pure substance and specifically an element. It is made entirely of iron atoms and cannot be broken down into simpler substances through chemical reactions. Iron is represented by the symbol Fe on the periodic table and has consistent physical and chemical properties.
- Carbon monoxide (CO) is classified as a pure substance and a compound. It consists of one carbon atom covalently bonded to one oxygen atom. This compound has a fixed ratio (1:1) of carbon to oxygen and exhibits consistent properties throughout, making it a pure substance. Carbon monoxide is important in various chemical reactions and is known for its toxic effects on humans and animals when inhaled.
In summary, each substance is identified based on its composition and properties, providing clarity on whether they are pure substances or mixtures and further classifying them appropriately.