Chapter 3 Minerals and Rocks (part 1 of 3)

Law of Constancy of Interfacial Angles (Steno's Law)

A law which states that the angle between equivalent faces of the same mineral is always the same.

Hardness

A mineral's resistance to scratching and abrasion.

Color

A phenomenon of light by which otherwise identical objects may be differentiated.

Proton

A positively charged subatomic particle found in the nucleus of an atom.

Density

A property of matter defined as mass per unit volume.

aggregates

A rock is any solid mass of mineral, or mineral-like, matter that occurs naturally as part of our planet. Most rocks, like the sample of granite, occur as _____ of several different minerals. The term _____ implies that the minerals are joined in such a way that their individual properties are retained

Octet rule

A rule which states that atoms combine in order that each may have the electron arrangement of a noble gas (that is, the outer energy level contains eight neutrons).

Mohs scale

A series of 10 minerals used as a standard in determining hardness.

Chemical bond

A strong attractive force that exists between atoms in a substance. It involves the transfer or sharing of electrons that allows each atom to attain a full valence shell.

Neutron

A subatomic particle found in the nucleus of an atom. The neutron is electrically neutral, with a mass approximately equal to that of a proton.

Compound

A substance formed by the chemical combination of two or more elements in definite proportions and usually having properties different from those of its constituent elements.

Element

A substance that cannot be decomposed into simpler substances by ordinary chemical or physical means.

element

All atoms with the same number of protons have the same chemical and physical properties. Together, a group of the same kind of atoms is called an _________.

atoms

All matter, including minerals, is composed of minute building blocks called _____—the smallest particles that cannot be chemically split.

chemically split

All matter, including minerals, is composed of minute building blocks called atoms—the smallest particles that cannot be ___________

Periodic table

An arrangement of the elements in which atomic number increases from the left to right and elements with similar properties appear in columns called families or groups.

Ion

An atom or a molecule that possesses an electrical charge.

Fracture

Any break or rupture in rock along which no appreciable movement has taken place.

mineral

Any naturally occurring inorganic solid that possesses an orderly crystalline structure and a definite chemical composition that allows for some variation.

rock

A ____ is any solid mass of mineral, or mineral-like, matter that occurs naturally as part of our planet.

chemical bond

A _______________ is the transfer or sharing of electrons that allows each atom to attain a full valence shell of electrons. Some atoms do this by transferring all their valence electrons to other atoms so that an inner shell becomes the full valence shell.

Ionic bond

A chemical bond between two oppositely charged ions that is formed by the transfer of valence electrons from one atom to the other.

Covalent bond

A chemical bond produced by the sharing of electrons.

Metallic bond

A chemical bond that is present in all metals that may be characterized as an extreme type of electron sharing in which the electrons move freely from atom to atom.

two or more elements

A few minerals, such as native copper, diamonds, sulfur, and gold, are made entirely of atoms of only one element. However, most elements tend to join with atoms of other elements to form chemical compounds. Most minerals are chemical compounds composed of atoms of ___________.

Tenacity

Describes a mineral's toughness or resistance to breaking or deforming.

octet rule

Atoms tend to gain, lose, or share electrons until they are surrounded by eight valence electrons.

electrons

Atoms, in turn, contain even smaller particles—protons and neutrons located in a central nucleus that is surrounded by _________

electrical charge

Both protons and electrons share a fundamental property called ________. Protons have an electrical charge of +1, and electrons have a charge of −1. Neutrons, as the name suggests, have no charge.

−1

Both protons and electrons share a fundamental property called electrical charge. Protons have an electrical charge of +1, and electrons have a charge of ____. Neutrons, as the name suggests, have no charge.

+1

Both protons and electrons share a fundamental property called electrical charge. Protons have an electrical charge of _____, and electrons have a charge of −1. Neutrons, as the name suggests, have no charge.

A linear zone of irregular topography on the deep-ocean floor that follows transform faults and their inactive extensions.

Fracture zone

Any natural solid with an ordered, repetitive atomic structure.

Crystal

DEFINITE CHEMICAL COMPOSITION

DEFINING A MINERAL: (1) NATURALLY OCCURRING (2) INORGANIC (3) SOLID (4) ORDERLY CRYSTALLINE STRUCTURE (5) _____

ORDERLY CRYSTALLINE STRUCTURE

DEFINING A MINERAL: (1) NATURALLY OCCURRING (2) INORGANIC (3) SOLID (4) _____ (5) DEFINITE CHEMICAL COMPOSITION

SOLID

DEFINING A MINERAL: (1) NATURALLY OCCURRING (2) INORGANIC (3) _____ (4) ORDERLY CRYSTALLINE STRUCTURE (5) DEFINITE CHEMICAL COMPOSITION

INORGANIC

DEFINING A MINERAL: (1) NATURALLY OCCURRING (2) _____ (3) SOLID (4) ORDERLY CRYSTALLINE STRUCTURE (5) DEFINITE CHEMICAL COMPOSITION

NATURALLY OCCURRING

DEFINING A MINERAL: (1) _____ (2) INORGANIC (3) SOLID (4) ORDERLY CRYSTALLINE STRUCTURE (5) DEFINITE CHEMICAL COMPOSITION

free

Electrical forces hold atoms together and bond them to each other. These electrical attractions lower the total energy of the bonded atoms, which, in turn, generally makes them more stable. Consequently, atoms that are bonded in compounds tend to be more stable than atoms that are ____(not bonded).

metallic bonds

In _______ the valence electrons are free to move from one atom to another so that all atoms share the available valence electrons

glass

Minerals have a repetitive, orderly arrangement of atoms, whereas substances such a _____have an unordered atomic structure.

chemical formula

Most minerals are chemical compounds having compositions that can be expressed by a ____.

Two or more minerals having the same chemical composition but different crystalline structures. Exemplified by the diamond and graphite forms of carbon.

Polymorphs

electrons

Protons and neutrons are very dense particles with almost identical masses. By contrast, _____ have a negligible mass, about 1/2000 that of a proton.

Habit or Crystal Shape

Refers to the common or characteristic shape of a crystal or an aggregate of crystals.

The relatively few minerals that make up most of the rocks in Earth's crust.

Rock-forming minerals

electrically neutral

Since matter typically contains equal numbers of positively charged protons and negatively charged electrons, most substances are ____________.

Luster

The appearance or quality of light reflected from the surface of a mineral.

Streak

The color of a mineral in powdered form

valence electron

The electrons involved in the bonding process; the electrons occupying the highest principal energy level of an atom.

chemical nature

The number of protons in the nucleus of an atom, called the atomic number, determines its ___ .

Specific gravity

The ratio of a substance's weight to the weight of an equal volume of water.

Principal shell

The shell or energy level an electron occupies.

Nucleus

The small, heavy core of an atom that contains all of its positive charge and most of its mass.

Atom

The smallest particle that exists as an element.

Cleavage

The tendency of a mineral to break along planes of weak bonding.

The smallest group of atoms, ions, or molecules that form the building block of a crystal.

Unit cell

covalent bond

When the electrons are shared between the atoms, the bond is a ____.

metallic

When the valence electrons are shared among all the atoms in a substance, the bonding is ____.

ionic bond

When the valence electrons are transferred between the elements to form ions, the bond is an ___.

hybrid bonds

many chemical bonds are actually ___ that exhibit some degree of electron sharing and some degree of electron transfer. Bonds can be found with almost every possible combination of covalent and ionic character. For example, silicate minerals are composed of silicon and oxygen atoms that are joined together with other elements by bonds that display characteristics of both ionic and covalent bonds.