Question

In the lab, I conducted tests and observed the physical properties of minerals. I combined my observations to identify the mineral samples based on their hardness, streak, color, and luster, and on how they break. I also identified rock samples based on their physical properties, such as grain size and foliation. I learned that the properties that are used to classify or group minerals and rocks can also be used to identify them. I also learned that the physical properties of rocks can tell us how they were formed. Which idea is NOT included in the answer?

A) Properties used to classify minerals and rocks
B) How to identify rocks based on physical properties
C) The history of mineral classification
D) The relationship between physical properties and rock formation

Answer 1

The student's observations in the lab focused on the physical properties of minerals and rocks, such as hardness and grain size, for the purpose of identification and classification, not the history of mineral classification.

Step-by-step explanation:

The idea not included in the student's answer is C) The history of mineral classification. When discussing observable properties for identifying minerals and rocks, the history of how these classification systems were developed is not covered. The observations mentioned focus on the physical properties like hardness, streak, color, and luster, as well as how rocks break, their grain size, and foliation. These properties help geologists determine how the rocks were formed without needing high-tech lab equipment for chemical analyses. The physical properties can also reveal the rock's depositional environment and the grade of metamorphism if applicable.

Physical properties are characteristics observed or measured without changing the substance's identity. While chemical properties describe how a substance can undergo a chemical change, these were not the focus of the student's lab work. The student's tasks involved examining physical properties such as color, density, and electrical conductivity, which are crucial for classifying and identifying rocks and minerals. Moreover, physical changes, which do not alter the substance's chemical composition like melting or dissolving, must be distinguished from chemical changes which result in the formation of new substances.