ch 2

In order for a particular type of material to be classified as a mineral, it must ____.

-be a solid, occur naturally, have a crystalline structure & have a definite chemical composition

____ bonding occurs when electrons are shared between adjacent atoms.

covalent_

The mineral ______ forms through the interaction of the hydrosphere and atmosphere (via evaporation).

halite

The most common rock-forming minerals are almost entirely made up of just eight (8) different elements. In order of greatest abundance to least abundance (by weight), what are the top 4 most common elements found in Earth's crust?

oxygen, silicon, aluminum, and iron

Which of the following minerals is the only one to be made up entirely of silicon & oxygen?

quartz

Why is there a difference in hardness between the two polymorphs of crystalline carbon, diamonds and graphite?

The crystalline structure of graphite forms sheets with weak bonds between each sheet while the covalent bonds of a diamond are three-dimensional and strong in every direction.

The property of some minerals which allows them to be broken cleanly along a plane of weak bonding in their molecular structure is referred to as ______.

cleavage

When quartz is broken, it often exhibits a distinctively curving fracture surface similar to that of broken glass. This is known as:

conchoidal fracture

The characteristic shape formed by the crystal growth of a particular mineral is known as its _________.

crystal form (aka "habit")

A mineral that cannot be broken cleanly along a well defined plane (and thus is presumed to have equally strong chemical bonds in all directions) is said to exhibit a property called ______.

fracture

A(n) _________ bond is formed when electrons are exchanged between atoms to form oppositely charged ions that will bond together.

ionic

The mineral property defined by the apperance and/or quality of light reflected from the surface of a mineral is known as ______.

luster

Why do the mica minerals (biotite and muscovite) exhibit one plane of cleavage, while quartz exhibits no cleavage at all?

micas are sheet silicates and tend to cleave along the weaker planes between sheets; quartz is a framework silicate with strong bonds in all directions

The two most abundant elements in Earth's crust are __.

oxygen and silicon

An unstable isotope is one that will experience changes in its nuclei, releasing energy and subatomic particles. The energy released is what we know as:

radioactivity

The most common group of rock-forming minerals are the ______.

silicates

The most common minerals in the Earth's crust are the _______.

silicates

A pulverized mineral (usually on a piece of white unglazed porcelain) gives a color called its ____, that is usually more reliable than the color of the specimen itself.

streak

Which of the following special properties is one that is particularly unique to plagioclase feldspars?

striations

A mineral is defined as a crystalline solid that is naturally occurring, has a specific chemical composition and forms through geologic processes. true/false

true

true/false Metallic bonding allows electrons to be shared freely among all the atoms within the substance instead of just between two adjacent atoms.

true