Coefficient of cubical expansion

The general equation which is applicable to linear, superficial or cubical coefficients of expansion, may be expressed as mt m (I + t + /3d2 + yt3 + where mt = length, area or volume at t°C m0 = same at temp 0°C a fit y = empirically detd coefficients For solids, if. a linear coeff 0O is known, the superficial coeff is approx (2fO and the cubical (W... 

The linear coefficient of expansion of a bar of polymer may be determined by measuring the difference in its length at two different temperatures and dividing by the temperature difference. The cubical coefficient of expansion may be measured in a dilatometer such as that used for measuring Tr... 

NIST has specified 20°C as the normal temperature for volumetric work. The cubical coefficient of expansion of Pyrex is about 0.9 X 10 K that of water at 20°C is about 21 X 10 K. The expansion of glass will be of importance only in very precise work that of water however will affect molar concentrations and will be of significance if the actual temperature is more than about 5°C removed from 20°C. 

Its cubical coefficient of expansion with rise of temperature is 0 00004.1... 

Tabie 3.35. PTFE Resins Cubical Coefficients of Expansion ... 

The theory of the method is as follows. Consider the effect of temperature upon the proportion of the tube occupied by liquid. Let F be the fraction occupied by liquid, V the internal volume of the tube, m the mass of substance present, py and p are the densities of vapour and liquid respectively, and a the cubical coefficient of expansion of glass, and let the subscripts 0 and T refer to room temperature and temperature T respectively. 

Figure 8.18 Isochronous volumes of poly(vinyl acetate) at two times, 0.02 h and 100 h, after quenching to various isothermal temperatures (59). Also shown is the cubic coefficient of expansion, a, measured at the 0.02 h cooling rate.

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