In thermodynamics, the triple point of a substance is the temperature and pressure at which the three phases (gas, liquid, and solid) of that substance coexist in thermodynamic equilibrium. For example, the triple point of mercury occurs at a temperature of ?38.83440 °C and a pressure of 0.2 mPa.
In addition to the triple point for solid, liquid, and gas phases, a triple point may involve more than one solid phase, for substances with multiple polymorphs. Helium-4 is a special case that presents a triple point involving two different fluid phases (lambda point).
The triple point of water is used to define the kelvin, the base unit of thermodynamic temperature in the International System of Units (SI). The value of the triple point of water is fixed by definition, rather than measured. The triple points of several substances are used to define points in the ITS-90 international temperature scale, ranging from the triple point of hydrogen (13.8033 K) to the triple point of water (273.16 K, 0.01 °C, or 32.018 °F).
The term "triple point" was coined in 1873 by James Thomson, brother of Lord Kelvin. Wikipedia, Triple Point
See Also
apex point of collision
associative point
atomic triplet
atomic triplets
beginning point
beginning points
binary triplet
boiling point
cathode dividing point
center point balance equilibrium fulcrum
centering point
centering point of stillness
central point
collision point
dimensionless pinpoint of space
Figure 12.04 - Locked Potential Points Relations and Descriptions
Figure 13.08 - Triple Streams of Electricity
Figure 14.03 - A section from one of Keelys charts showing his generous use of Triplets
Figure 14.07 - Love Principle: Two sympathetic waves expanding from two points have one coincident centering locus
Figure 14.12 - Triple Equations to Represent a Single Sympathetic Event
Figure 16.09 - Triple Streams of Electricity
Figure 2.10 - Triple Dual Vectors - In Rotary Motion
Figure 2.5 - Non-Point of Proto-Beginning
Figure 2.6 - Non-Point nothingness becoming All that Is
Figure 4.1 - Triple Cardinal Directions Vectors or Dimensions
Figure 4.13 - Triplet Originations and Centralizations of Matter
Figure 4.14 - Feynmans Triplet Structures of the Proton and Neutron
Figure 4.3 - Single Mode Electric Vector Generating Circular Motion also Shown within Triple Vectors
Figure 4.3 - Single Mode Electric Vector Generating Circular Motion also Shown within Triple Vectors - See Also
Figure 4.4 - Triple Vectors in Orthogonal Motions
Figure 4.6 - Triple Vectors in Motion on Triple Planes
Figure 4.7 - Triple Planes and Polar Vectors of Motion
Figure 4.8 - Triple Polar Rotations In and Out
Figure 6.14 - Triple Three Cubes
Figure 6.4 - Triple Interior Planes
Figure 6.5 - Triple Planes - May Underlay some Sacred Geometry or Religious Concepts
Figure 6.6 - Russells Multiple Views of Tripleness
Figure 7.3 - Step 3 - Sphere Forms Orthogonally Triple Compressing Shell Layers
Figure 7B.05 - Triplet Forming a Unity
Figure 7B.06 - Rotating Triplets Animation
Figure 7B.09 - Feynmans Triplet Structure of Photon
Figure 7B.15 - Triple Planes relative to Center
Figure 9.8 - Triple Centers
focal point
focalizing point
freezing point
high pressure hot points of gravitative centres
high pressure point of dense mass
interetheric point
melting point
Musical Triplet
pair of gravity points
pair of points
pairs of gravity points
pinpoint of space
point
point of focalization
point of north
point of rest
point of south
point of stillness
point of suspension
sequence of points of stillness
series of points in space which form a shaft
shafts made up of many points
Smoke Point
still point
still point of gravity
sympathetic triple stream
Table 13.02 - Vibratory and Oscillatory Triple Force Functions
triple
triple association
Triple Axial Vectors
Triple Centers
triple circuit ring
Triple Concentration
triple connective links
triple currents
Triple Flows
triple focalized action
triple impulses
triple inertia planes
triple nodal transmitter
Triple Planes
Triple Polarization
triple subdivision
triple sympathetic vibratory impulse
Triple Triplet
Triple Triplet Flows
triple union
triple vacuum evolutions
triple-triple
Triple-triple Charts
Triplet
Triplet Attraction
Triplet Rotation
Triplet Swirl
Twenty-seven depolar triple groupings
two controlling points of stillness
two points of stillness
two-way extension of a point in space
ultramicroscopic point
white invisible still point
X-Points
Zero Point
Zero point energy
zero points of stillness
13.06 - Triple Currents of Electricity
13.11 - Triple Currents and Streams
13.31 - Polarization Points
14.36 - Triple Equations
16.29 - Triple Currents of Electricity
3.16 - Neutral Centers as Points of Action
4.1 - Triple Vectors
4.2 - Triple Vectors and Rotation
4.5 - Triple Rotary or Vortex Motions
4.9 - Triple Contractive Motions
7B.04 - Triplets Form Larger Units of Unity
7B.05 - Rotating Triplets