CHEMISTRY GLOSSARY

hybridization    →   hibridizacija

Hybridization is an internal linear combination of atomic orbitals, in which the wave functions of the atomic orbitals are added together to generate new hybrid wave functions. The new orbitals which are formed are hybrids of the originals and have properties (shape, size and energy) that are somewhere in between.

inertia    →   inercija

Inertia is an expression for the tendency of all bodies to resist motion, or to continue in motion if already moving. If a body undergoes linear motion (translation), inertia corresponds to the mass of the body. In order to express inertia of a rotating body, the so-called rotational inertia is defined as suitable physical quantity. A bowling ball has more inertia than a tennis ball, due to its higher mass.

ionic radius    →   ionski radijus

Ionic radius is the radius of anions and cations in crystalline ionic compounds, as determined by consistently partitioning the center-to-center distance of ions in those compounds. In general, negative ions have larger ionic radii than positive ions.

lithosphere    →   litosfera

Lithosphere (from the Greek for rocky sphere) is rigid, rocky outer layer of the Earth, consisting of the crust and the solid outermost layer of the upper mantle. The distinguishing characteristic of the lithosphere is not its composition but its flow properties. It floats on the asthenosphere, which is the heat-softened layer of the mantle below the lithosphere.

The lithospheric is not one continuous piece but is broken into about a dozen major separate rigid blocks, or plates, which move independently relative to one another. This movement of lithospheric plates over the asthenosphere is described as plate tectonics. When an oceanic plate and a continental plate meet, the heavier oceanic plate (composed mostly of basalt, specific gravity about 3.0 or peridotite, specific gravity about 3.3) subducts under the lighter continental plate (composed mostly of granite, specific gravity about 2.7).

mass fraction    →   maseni udio

Mass fraction (w_A) is the ratio of the mass of substance A to the total mass of a mixture.

measuring cylinder    →   menzura

Measuring cylinders (graduated cylinders) are graduated glass cylinders with a capacity from 2 mL to 2 L. They are used when reagent solutions for volume measuring are prepared when accuracy is not of great relevance. The larger the measuring cylinder, the bigger the measuring error.

Nusselt number    →   Nusseltova značajka

Nusselt number (Nu) is a dimensionless quantity used in fluid mechan-ics, defined by

where h is coefficient of heat transfer, l is length, and k is thermal conductivity.

Peclet number    →   Pecletova značajka

Péclet number (Pe) is a dimensionless quantity used in fluid mechanics, defined by

where v is velocity, l is length, and a is thermal diffussivity.

power    →   snaga

Power is the rate at which work is done. If a force does work W in a time interval Δt, the average power is:

Instantanous power is the instantaneous rate of doing work:

Like work, power is scalar quantity. Its SI unit is watt (W); 1 W=1 J s^-1.

Prandtl number    →   Prandtlova značajka

Prandtl number (Pr) is a dimensionless quantity used in fluid mechanics, defined by

where η is viscosity, ρ is density, and a is thermal diffusivity.