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Showing 1621–1650 of 1709 reference entries

Chemistry · PhysicsIntensive, extensive, specific and molar properties

Scaling the system amount is different from changing its state.

DefinitionChemistry · MeasurementRelative atomic mass and isotope composition

Relative atomic mass is dimensionless and depends on the isotope composition being averaged.

DefinitionChemistry · MeasurementMolar mass and mass–amount conversion

Molar mass converts a specified substance's amount into mass.

DefinitionChemistry · MeasurementAmount concentration, molality and composition fractions

Concentration must declare its numerator and denominator.

DefinitionChemistryDilution conserves the retained solute amount

Dilution arithmetic refers to final solution volume, not the amount of solvent poured in.

MethodChemistryLimiting reagent, theoretical yield and percent yield

Stoichiometry gives a maximum under a specified reaction model; recovery measures the actual yield.

MethodChemistryFormal charge is equal-share electron accounting

Formal charge, oxidation state and partial charge answer different questions.

DefinitionChemistryElectrolyte strength, solubility and concentration

Strong describes ion formation by dissolved solute, not how much solute dissolves.

DefinitionChemistryComplete ionic and net ionic equations

Cancel unchanged species while conserving both atoms and charge.

MethodBiology · ChemistryWater polarity and biological interactions

Water's molecular interactions help explain solvation, cohesion and thermal buffering.

Empirical findingBiologyCell size and surface-to-volume scaling

For geometrically similar cells, volume grows faster than surface area.

ModelBiology · ChemistryOsmolarity and tonicity

Total particle concentration and lasting cell-volume effect are different properties.

DefinitionBiologyChromosome sets and DNA content

DNA replication doubles DNA content without doubling chromosome-set ploidy.

DefinitionBiologyOrganisms, populations, communities and ecosystems

Ecological levels describe different interacting sets and environments.

DefinitionBiologyPopulation size, density and demographic balance

Total individuals and individuals per area or volume must be distinguished.

ModelBiologyMutation and selection: different roles

Mutations do not generally appear because an organism needs their future advantage.

Empirical findingBiologyClades and rooted-tree interpretation

Shared ancestry is represented by topology, not by the left-to-right order of tips.

MethodBiology · ChemistryPlant water potential and pressure balance

Osmotic and mechanical contributions together determine passive water movement.

ModelEarth & cosmosRock and mineral are different material categories

A mineral species and a rock aggregate have different identifying features.

DefinitionEarth & cosmosEarth's compositional and mechanical layers

Crust–mantle–core and lithosphere–asthenosphere partition Earth by different properties.

ModelEarth & cosmos · MeasurementGeodetic latitude, longitude and reference systems

A coordinate pair needs a reference surface, origin and convention.

DefinitionEarth & cosmos · MeasurementMap projections and distortion

Flattening Earth's curved reference surface requires a choice of distortions.

ModelEarth & cosmos · MeasurementEllipsoid height, geoid and orthometric height

Height above a geometric reference is not automatically height above a gravity reference.

DefinitionEarth & cosmosRotation, axial tilt and seasonal sunlight

Axial tilt changes the angle and duration of sunlight in opposite hemispheres.

ModelEarth & cosmosNatural hazard and disaster risk

A harmful physical process and the potential losses it creates are different quantities.

DefinitionEarth & cosmosUsing present processes to infer Earth's past

Modern process evidence informs geological interpretation only with the past boundary conditions.

MethodEarth & cosmosLunar phases and synchronous rotation

Phases change the visible illuminated fraction; they are not Earth's shadow moving across the Moon.

ModelEarth & cosmosSolar and lunar eclipse geometry

New or full Moon is necessary for the corresponding eclipse but does not guarantee alignment.

ModelEarth & cosmosIAU Solar-System body categories

A scoped naming convention distinguishes planets, dwarf planets, small bodies and satellites.

DefinitionEarth & cosmos · MeasurementAstronomical unit and light-year

The astronomical unit and light-year measure lengths, with different defining conventions.

Definition
DefinitionSource checked

Natural hazard and disaster risk

Earth & cosmos

A harmful physical process and the potential losses it creates are different quantities.

Key knowledge

A hazard is a process, phenomenon or activity with the potential to cause harm. Disaster risk concerns potential losses over a specified period and depends on the hazard together with exposure, vulnerability and capacity. The same physical event can therefore produce different risk and consequences in different settings; an intense hazard alone does not specify a disaster's losses.

Conditions and scope

  • Specify location, time period, affected people/assets and the probability or scenario model.
  • This terminology does not supply a universal numerical multiplication formula, an individual event prediction or an operational warning.
Sources · 2

References

Sources retain their recorded scope. A source link alone does not establish verification of every statement.

  1. UNDRR2 sources
    1. Sendai Framework terminology (2017): hazardUNDRRReference guideundrr.orgRead source
    2. Sendai Framework terminology (2017): disaster riskUNDRRReference guideundrr.orgRead source

Evidence and review

Inspected both UNDRR definition/annotation bodies, including hazard characterization and risk's exposure/vulnerability/capacity dependence. Uses the terminology distinction without inventing universal quantified loss or response rules.

2026-10-10 · Independent Mathematics and Information editor (/root/core_math_information). Independent AI editorial review of this entry's statements, equations, applicability conditions and source coverage. Source checks apply to these claims within their stated limits.

Related reference entries

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Showing 1–2 of 2 relationships

Scientific relationships · 2 / 2

The relationship type describes the connection. Its linked statements, sources and conditions define the scope.

  1. Related to
    Relationship sources · 2

    Linked statements

    • A hazard is a process, phenomenon or activity with the potential to cause harm. Disaster risk concerns potential losses over a specified period and depends on the hazard together with exposure, vulnerability and capacity. The same physical event can therefore produce different risk and consequences in different settings; an intense hazard alone does not specify a disaster's losses.

    Tectonic processes can generate hazards; resulting disaster risk additionally depends on exposed and vulnerable systems.

  2. Related to
    Relationship sources · 2

    Linked statements

    • An earthquake's hypocenter or focus is the point where rupture initiates; its epicenter is the surface point above that origin. A fault rupture extends over an area, so its epicenter does not locate all slip. A magnitude characterizes source size using a specified scale, whereas intensity describes shaking effects at a particular location. One earthquake can therefore have different local intensities. Distance, source depth and rupture direction, propagation and local ground conditions affect those differences.

    A local shaking effect is one hazard observation; exposure and vulnerability also enter risk.

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