Question

the diagram shows a mercury glass thermometer containing nitrogen,, graduated on the Kelvin or absolute scale. bp. = 633K, mp.= 230K, softening point of glass= 750K
a) give the reason why why the scale need not to be graduated below the mark 200
b) give oine advantage of hvin nitrogen in the tube rather than vaccum.
c) give a reason why the scale is not graduated above the 700 mark.

Answer 1

a)Because at 234.32 K, -38.83 . C, -37.89 . F mercury crystallizes / melts
b)In vacuum, the mercury will evaporate quickly and cool at the same time Mercury
has not evaporated, it is additional error in measuring
c)Because at 629.88 K, 356.73 . C, 674.11 . F mercury boils/condenses