Rocks And Minerals Quiz

Minerals and rocks are not the same. A mineral is an inorganic solid substance with a specific chemical composition and atomic arrangement. On the other hand, a rock is a solid mixture of two or more minerals. Therefore, the given answer correctly explains the difference between a rock and a mineral.

Igneous rocks form when magma from inside the earth cools. Magma is molten rock that is located beneath the earth's surface. When it cools and solidifies, it forms igneous rocks. This process can happen either underground or on the earth's surface. If the magma cools underground, it forms intrusive igneous rocks, such as granite. If the magma reaches the earth's surface and cools quickly, it forms extrusive igneous rocks, such as basalt. Therefore, the correct answer is when magma from inside the earth cools.

Rocks are composed of minerals, which are naturally occurring inorganic substances. The question asks how many minerals are put together to form rocks. Since rocks can be made up of different combinations of minerals, it is correct to say that rocks are made of 2 or more minerals put together.

Color is the most unreliable source to identify a mineral's property because many minerals can have the same or similar colors. For example, both quartz and calcite can be found in various colors such as white, pink, or yellow. Therefore, relying solely on color to determine a mineral's identity can lead to inaccurate results. It is important to consider other properties like streak, luster, and hardness for a more reliable identification.

When extrusive igneous rocks cool rapidly, the molten rock solidifies quickly, trapping gas pockets called vesicles within the rock's structure. This occurs because the rapid cooling does not allow enough time for the gas bubbles to escape. As a result, the vesicles become trapped and are preserved in the rock as it solidifies.