Chem Test 4

Front 1

What is the difference between intramolecular forces and intermolecular forces?

Back 1

intramolecular forces (dispersion forces, dipole-dipole interactions and hydrogen bonds) : affect chemical properties
intermolecular forces(metallic, covalent, ionic bonding): affect physical properties

Front 2

What properties of matter do intra/inter molecular forces affect?

Back 2

Affect boiling/melting points, solubility

Front 3

Discuss how intermolecular forces affect physical phenomena like surface tension, capillary action and viscosity.

Back 3

Viscosity: related to the ease with which individual molecules of the liquid can move with respect to one another. Increases with molecular weight
tension: imbalance of intermolecular forces at the surface of a liquid; stronger bonds=greater surface tension
capillary action: force on the liquid at the edges and result in a meniscus which turns upward.

Front 4

What is the difference between a crystalline solid and an amorphous solid?

Back 4

crystalline: highly regular arrangements of their components. There are three types of crystalline solids; ionic, molecular, and atomic.

Amorphous solid:a solid with considerable disorder in its structure.

Front 5

What is a lattice in a crystalline solid?

Back 5

crystal lattice: network of points on which the repeating unit of the structure of a solid may be imagined to be laid down so that the structure of the crystal is obtained

Front 6

What is a unit cell in a crystalline solid?

Back 6

Smallest portion of a crystal that reproduces the structure of the entire crystal when repeated in different directions in space

Front 7

What are the seven different types of unit cells in crystal and which is the one which most commonly occurs?

Back 7

Cubic, tetragonal, orthorhombic, monoclinic, hexagonal, rhombohedral, triclinic

Cubic is more common

Front 8

how do crystalline solids adopt their structures in terms of the
Close Packing of Spheres model.

Back 8

close packing: Each sphere is surrounded by six others in the layer, a second layer of spheres can be placed on the first, and then a third. Bring particles in closest contact to maximize attractive forces.

Front 9

What are the differences between cubic close packing and hexagonal close packing that occurs in solids?

Back 9

Hexagonal: spheres of the third layer are placed in line with those of the first
Cubic: Fourth layer repeats the first layer

Front 10

Identify the three general classes of solids

Back 10

Ionic, Molecular, Atomic

Front 11

Explain how the lattice energies of ionic solids affect their melting points.

Back 11

The more closely packed the arrangement of metal atoms, the stronger the bond = higher melting point

Front 12

Explain how the attractive forces among solids affect their hardness and malleability.

Back 12

delocalized electrons in the sea of electrons enable metal atoms to roll over each other when stress is applied

Front 13

Explain the difference between graphite and diamond in terms of bonding and attractive forces among its carbon atoms.

Back 13

Diamond: each carbon atom is bonded tetrahedrally to four other carbon atoms (sp3 orbital bonding)
Graphite: carbon atoms in trigonal planar geometries to three other carbons (sp2 orbital bonding)

Front 14

What is the difference between a rock and a mineral?

Back 14

Rock: rock is a solid combination of more than one mineral formations

Mineral: most metallic elements found in nature as solid inorganic compounds

Front 15

What is an ore and in what portion of the earth are they mined to obtain the metals we use?

Back 15

Ore: deposits that contain metals in economically exploitable quantities
Found in lithosphere

Front 16

What is the rock cycle?

Back 16

Magma - cooling/solidification -> Igneous - weathering -> Sediment -cementation/compaction -> sedimentary - heat and pressure -> metamorphic - melting -> magma

Front 17

What are the two broadest classifications of minerals?

Back 17

Silicates and nonsilicates

Front 18

What is the basic unit of structure of all silicate minerals?

Back 18

silicon atom surrounded in a tetrahedral fashion by oxygen

Front 19

What is the formula for the basic unit of silicates?

Back 19

SiO4^(4-)

Front 20

What are the different types of silicate structures that can be constructed from the back units found in silicates?

Back 20

two tetrahedra sharing and oxygen make a disilicate ion
Large number of silicate tetrahedra linked together to form chains

Front 21

General term applied to a group of fibrous silicate minerals in which the sheets are formed into rolls

Back 21

Asbestos

Front 22

What is metallurgy?

Back 22

the science and technology of extracting metals from their natural sources and preparing them for practical use

Front 23

What are the four basic steps in all metallurgical processes?

Back 23

mining, concentrating the ore, reducing the ore to obtain free metal, refining or purifying the metal, mixing the metal with other elements

Front 24

Process involves use of high temp and special ovens or kilns

Back 24

Pyrometalurgy

Front 25

Thermal treatment that causes a chem reaction between the ore and heated air in a furnace or kiln. Primarily used for sulfides

Back 25

Roasting

Front 26

Utilizes aqueous solutions to extract metals from ores

Back 26

Hydrometallurgy

Front 27

Metal containing ores is dissolved in an agent, Primarily used to separate gold and aluminum from low grade ore (type of Hydrometallurgy)

Back 27

Leaching

Front 28

Process used to refine metals from ores by passing an electrical current through a solution

Back 28

Electrometallurgy

Front 29

Production of Al from Bauxite ore

Back 29

Bayer process
Separates Al2O3 from the impurities before the metal is recovered. Type of Hydrometallurgy

Front 30

A process used to obtain aluminum by electrolysis of Al2O3 dissolved in molten Na3AlF6

Back 30

Hall-Heroult process

Front 31

In commercial preparation of sodium, molten NaCl is electrolyzed in this

Back 31

Downs Cell

Front 32

Material that contains a mixture of two or more elements having the characteristics of a metal

Back 32

alloy

Front 33

name some common alloys

Back 33

Bronze (copper + tin)
Brass (copper + zinc)
Stainless Steel (iron + chromium)

Front 34

homogeneous mixtures where component elements are dispersed randomly and uniformly

Back 34

Solution Alloys

Front 35

Consisting of layers of the elements formed by rapid cooling

Back 35

Heterogeneous Alloys

Front 36

Homogeneous alloys having a highly ordered distribution of its atoms

Back 36

Intermetallic compounds

Front 37

Deterioration of metals by an elecrochemical process

Back 37

corrosion

Front 38

Explain the iron corrosion process

Back 38

1. a region of the metal's surface serves an an anode where oxidation occurs
2. Reduciton of O2 to H2O at the cathode
3. The Fe2+ ions are further oxidized to form rust

Front 39

What are five methods to protect metals from corrosion?

Back 39

1. Coat metals with paint
2. Passivation (metals treated with strong oxidizing agent)
3. Alloying (stainless steel)
4. cover active metal with a thin layer of an inactive metal
5. Cathiodic protection