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Showing 241–270 of 284 reference entries

ChemistryRNA-condensate interfaces: 2025 evidence

The RNA-condensate interface study measures in-vitro RNA/PEG systems and compares interface behavior with molecular modeling.

Empirical finding
ChemistryCondensate function versus correlated assembly

Assembly, partitioning and a cellular phenotype do not alone identify whether phase separation causally produces that phenotype.

Open question
ChemistryTernary degradation complexes and independent controls

Gadd and colleagues resolved a Brd4 bromodomain–MZ1–VHL complex and combined binding, mutagenesis, proximity and cell-protein measurements.

Empirical finding
Physics · ChemistrySurface tension and capillary rise

Interface forces can support pressure jumps and capillary columns.

Model
Physics · ChemistryHeat, temperature and specific heat

Heat is energy transferred because of a temperature difference.

Model
Physics · ChemistryPressure–volume work and process paths

Boundary work depends on the process, while internal energy is a state function.

Model
Physics · ChemistryReversible adiabatic ideal-gas relations

The power law needs an ideal gas and constant heat-capacity ratio.

Model
Physics · ChemistryReversible and quasistatic processes

Restoring the system alone does not establish reversibility.

Model
Physics · ChemistryEntropy change and reversible heat transfer

Use a reversible comparison path to calculate a state-function change.

Model
Physics · ChemistryMean free path in a dilute hard-sphere gas

A collision length depends on number density and cross section.

Model
Measurement · ChemistrySelectivity of a measuring system

Responding to a target differs from excluding interference.

Definition
ChemistrySubstances, elements, compounds and mixtures

Chemical composition and spatial uniformity describe different features of matter.

Definition
ChemistryPhysical change and chemical change

A change of phase need not change chemical identity.

Definition
ChemistryEmpirical, molecular and structural formulas

A formula's subscripts represent different information in different chemical models.

Definition
Chemistry · PhysicsIntensive, extensive, specific and molar properties

Scaling the system amount is different from changing its state.

Definition
Chemistry · MeasurementRelative atomic mass and isotope composition

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

Definition
Chemistry · MeasurementMolar mass and mass–amount conversion

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

Definition
Chemistry · MeasurementAmount concentration, molality and composition fractions

Concentration must declare its numerator and denominator.

Definition
ChemistryDilution conserves the retained solute amount

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

Method
ChemistryLimiting reagent, theoretical yield and percent yield

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

Method
ChemistryFormal charge is equal-share electron accounting

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

Definition
ChemistryElectrolyte strength, solubility and concentration

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

Definition
ChemistryComplete ionic and net ionic equations

Cancel unchanged species while conserving both atoms and charge.

Method
Biology · ChemistryWater polarity and biological interactions

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

Empirical finding
Biology · ChemistryOsmolarity and tonicity

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

Definition
Biology · ChemistryPlant water potential and pressure balance

Osmotic and mechanical contributions together determine passive water movement.

Model
Physics · ChemistryOpen, closed, isolated and adiabatic systems

A system boundary determines which transfers count as exchanges.

Definition
Measurement · Physics · ChemistryCommon non-SI units and exact SI conversions

Common non-SI unit names require their correct SI scale factors.

Definition
Physics · ChemistryGas pressure as molecular momentum transfer

Molecular collisions link macroscopic pressure to random translational motion.

Model
Chemistry · PhysicsOrdinary aggregate states and bulk behavior

Solid, liquid and gas describe bulk behavior rather than chemical identity.

Model