Chapter 13States of Matter

Liquids and SolidsChanges of State

Objectives

• Liquid (13.2)– How the atoms are arranged– Basic properties

• Solids (13.3)– How the atoms are arranged– Basic properties

• Changes of State (13.4)– What does equilibrium mean?– Le Chatelier’s Principle (We will talk more in another unit)– The six basic phase changes– Be able to describe the parts of a heating and cooling curve– Understand a phase diagram

The Four States of Matter

Plasma

Solid

Liquid

Gas

The Fifth Phase of Matter

Bose-Einstein Condensate

A Bose–Einstein condensate (BEC) is a state of matter of a dilute gas of bosons cooled to temperatures very near absolute zero (0 K or −273.15 °C). This state of matter was first predicted, generally, in papers by Satyendra Nath Bose and Albert Einstein in 1924–25.

The Fifth Phase of Matter1925 - Einstein extended Bose’s work and proved mathematically that cooling bosonic atoms to a very low temperature would cause them to fall (or "condense") into the lowest accessible quantum state, resulting in a new form of matter.

1938 - Fritz London proposed BEC as a mechanism for superfluidity in liquid helium and superconductivity.

1995 - The first BEC was produced by Eric Cornell and Carl Wieman at the University of Colorado at Boulder NIST–JILA lab, using a gas of rubidium atoms cooled to 170 nanokelvin (nK) (1.7×10−7 K). For their achievements Cornell, Wieman, and Wolfgang Ketterle at MIT received the 2001 Nobel Prize in Physics.

2010 - The first photon BEC was observed.

Dec. 2012 – Hydroxyl group (OH-) cooled to near-zero. Opens the door to possible BECs of dipolar radicals (anions).

What is a Bose-Einstein Condensate?

What determines which state of matter you are in?

Particle arrangementEnergy of the particlesDistance between particles

STATES OF MATTERSOLIDS

•Particles of solids are tightly packed, vibrating about a fixed position.

•Solids have a definite shape and a definite volume.

STATES OF MATTERLIQUID

Particles of liquids are tightly packed, but are far enough apart to slide over one another.

Liquids have an indefinite shape and a definite volume.

STATES OF MATTERGAS

Particles of gases are very far apart and move freely.

Gases have an indefinite shape and an indefinite volume.

Compression of Gases, Liquids and Solids– Gases are compressible fluids. Their molecules

are widely separated.– Liquids are relatively incompressible fluids.

Their molecules are more tightly packed.– Solids are nearly incompressible and rigid.

Their molecules or ions are in close contact and do not move.

Properties of Liquids

• Relative High Density• Relative Incompressibility• Ability to diffuse• Surface Tension• Viscosity• Capillary Action• Vaporization (Evaporation and Boiling)• Freezing

Properties of Solids• High Density• High Incompressibility• Definite Melting Point• Low Rate Of Diffusion• Amorphous versus Crystalline

Homework

• Homework #60 13.2 Section Review WS• Homework #61 13.3 Section Review WS