is: one of three processes (the other two being convection and radiation) in which heat can be transferred. [P7.3]
is operative: only in materials (gases, liquids and solids), i.e. not in a vacuum. [P7.3]
takes place: at the atomic level, through energy being passed from atom to atom by vibration and/or collision. [P7.3]
is driven: at the macroscopic level, by a temperature gradient, with heat being transferred from high temperature to low temperature. [P7.3, P7.5]
therefore is: a transport process. [P7.5]
sometimes is quantified: by Fourier's law. [P7.3]
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