An electric bulb of 250cc was sealed off at a pressure 10−3 mm of Hg and temperature $27^{0}$ C. The number of molecules present in the gas is
An electric bulb of volume 250 cc was sealed during manufacturing at a pressure of 10−3 mm of mercury at 270C. Compute the number of air molecules contained in the bulb. Avogadro constant= 6 × 1023 mol−1, density of mercury = 13600 kg m−3and g = 10 m s−2.