Module 2: Solids

Question 1

have definite shape and volume due to the compact arrangement of their particles

Answer 1

Solid

Question 2

have a regular, highly ordered arrangement

Answer 2

Crystalline Solid

Question 3

three dimensional pattern formed by the points representing the location of these particles

Answer 3

Space Lattice

Question 4

gradually soften once they are heated at a wide range of temperature

Answer 4

Amorphous Solid

Question 5

basic unit of crystal

Answer 5

Space Lattice

Question 6

smallest unit MIT of lattice that are stacked repeatedly to resemble the whole

Answer 6

Unit Cell

Question 7

number of particles present in a unit cell is the number of the nearest neighboring particles

Answer 7

Coordination Number

Question 8

coordination number identifies the physical properties such as _____ & ______

Answer 8

Density & Conductivity

Question 9

seven crystals systems

Answer 9

cubic, tetragonal, othorhombic, monoclinic, triclinic, rhombohedral (trigonal), hexagonal

Question 10

substances that crystallize in several arrangement

Answer 10

Polymorphous

Question 11

substance that crystallize in the same lattice with the same atomic arrangement

Answer 11

Isomorphous

Question 12

crystals that are the same in two dimensions but different in the third
can either be hexagonal or cubic-close packed

Answer 12

Polytypes

Question 13

give an ABCABC pattern of stacking

Answer 13

Cubic Closed-Packed

Question 14

gives an ABAB patterns oflayers resembling a hexagonal unit

Answer 14

Hexagonal Close-Packed

Question 15

tetrahedral hole

Answer 15

0.225r

Question 16

octahedral hole

Answer 16

0.414r

Question 17

determines the crystal structure of a solid
provides information on bond lengths and angles

Answer 17

X-ray Diffraction

Question 18

X-ray Crystallography

Answer 18

was pioneered by William Henry Bragg and William Lawrence Bragg

Question 19

ions occupy the unit cell
have high melting points ranging from 673-3273
hard, brittle, and poor conductors of heat and electricity

Answer 19

Ionic Solid

Question 20

the unit cell is made up of molecules or atoms
have low melting point, ranging from 1-673k
poor conductor of heat and electricity

Answer 20

Molecular Solid

Question 21

coordination number of ionic and molecular solid

Answer 21

6

Question 22

giant molecules which contain a very large number of atoms
high melting point, ranging from 1437-4273K

Answer 22

Network/Covalent Solid

Question 23

diamonds are _____ (different physical forms of the same element in the same physical state)

Answer 23

Allotropes

Question 24

bound by metallic bonding, a type of metal atoms “swim” in a sea of electrons
coordination number is 8 or 12
excellent conductors of heat, possess malleability, ductility, lusterm and hardness
melting point is from 234 to 3673K

Answer 24

Metallic Solid

Question 25

theory that explains the bonding in molecules by combining atomic orbitals

Answer 25

Molecular Orbital Theory

Question 26

extension of molecular orbital theory to solids, where overlapping atomic orbitals form energy bands

Answer 26

Band Theory

Question 27

movements of electrons in the Molecular Orbit Theory that are occupied by the conducting electrons

Answer 27

Conducting Bands

Question 28

do not conduct electricity due to the large gap between the empty MO and Conducting Bands

Answer 28

Insulators

Question 29

intermediate between the conductor and insulator

Answer 29

Semiconductors

Question 30

process of introducing a filled MO from a dopant between empty MO and conduction band

Answer 30

Doping

Question 31

allows a room in which electrons can move from the dopant’s filled MO to the empty MO of semiconductor

Answer 31

N-Doped

Question 32

allows a room in which electrons can move from the empty MO to the dopant’s MO

Answer 32

P-Doped

Question 33

entails either absorption or release of hear represented by a change in the latent heat of fusion occurs when substance is subjected to different temperature and pressure conditions involves the transition from one phase to another

Answer 33

Phase Change

Question 34

plot of temperature versus time at which a constant rate of energy is supplied onto the substance

Answer 34

Heating Curve

Question 35

process or continuing the boil at a liquid so that it will eventually vaporize or turn into gas liquid boils at 373K or around 100 degrees celsius

Answer 35

Vaporization

Question 36

process at which solid turns into has without undergoing its liquid phase

Answer 36

Sublimation

Question 37

solids with ____ vapor pressure easily sublime

Answer 37

high

Question 38

represents the pressure-temperature relationships are equilibrium, as the pure substance undergoes phase change in a closed system

Answer 38

Phase Diagram

Question 39

matter goes into the system and goes out into the surroundings

Answer 39

open system

Question 40

no exchange of matter takes place

Answer 40

Closed System

Question 41

represents the unique conditions under which all three phases exist in equilibrium together

Answer 41

Triple Point

Question 42

formed when the temperature of a substance is above its critical temperature

Answer 42

Supercritical Fluid

Question 43

temperature at which vapor cannot be liquified regardless of the pressure applied 647K or 372 degree celsius

Answer 43

Critical Temperature

Question 44

pressure at which liquidication occurs at the critical temperature

Answer 44

Critical Pressure

Question 45

combination of critical temperature and critical pressure

Answer 45

Critical Point

Question 46

critical point of water

Answer 46

647K or 2.21 x 10^7 Pa (218 atm)

Question 47

this is between liquid molecules that are responsible for the phenomenon known surface tension

Answer 47

Cohesive Forces

Question 48

this is the surface of the liquid when the cohesive forces between the liquid molecules are GREATER THAN the adhesive forces between the liquid and the walls of the container

Answer 48

Convex

Question 49

this is the surface of the liquid when the cohesive forces between the liquid molecules are LESSER THAN the adhesive forces between the liquid and the walls of the container

Answer 49

Concave

Question 50

greater the viscosity, the ______ the liquid flows

Answer 50

slower

Question 51

the larger the molecules, ________ the intermolecular forces and the ________ the viscosity

Answer 51

stronger, greater

Question 52

viscosity and temperature are _________ with each other

Answer 52

inversely proportional

Question 53

strong IMF, _______ vapor pressure

Answer 53

low

Question 54

temperature at which its vapor pressure is equal to the external or atmospheric pressure

Answer 54

Boiling Point

Question 55

boiling point increases as molar heat of vaporization _______

Answer 55

increases

Question 56

different molecular forms or various crystal modifications of a polymorphous element

Answer 56

Allotropes

Question 57

the manner in which these spheres are packed would give rise to unoccupied spaces in the crystal called _____

Answer 57

Holes

Question 58

solids that turns into liquid if it is heated

Answer 58

Melting

Question 59

the temperature at which a solid changes to a liquid a solid temperature at which the melting rate of a solid is the same as its freezing rate at a given pressure

Answer 59

Melting Point