Vapor pressure of mercury

The vapor pressure of mercury, P, also behaves kregulatly but may be obtained for temperatures from 0—150 °C by the following ... 

A bottle of mercury at 25°C was left unstoppered in a chemical supply room measuring 3.0 m by 3.0 m by 2.5 m. What mass of mercury vapor would be present if the air became saturated with it The vapor pressure of mercury at 25°C is 0.227 Pa. 

From Appendix E, the molar enthalpy of vaporization of mercury at the normal boiling point is 58.6 kJ/mol. Using the Clausius-Clapeyron equation to find the vapor pressure of mercury at 25°C, we have... 

The data in Table 8.4 [4] represent the vapor pressure of mercury as a function of temperature. Plot In P as a function of 1/T to a scale consistent with the precision of the data. If the resultant plot is linear, calculate AH Iz from the slope obtained by a least-squares fit to the line. If the plot is curved, use a numerical differentiation procedure to obtain the value of AHmjZ as a function of T, and calculate ACpm- See Appendix A for methods. 

TABLE 8.4. Vapor pressure of Mercury as a Function of Temperature... 

Using data from Table 6.2, calculate the vapor pressure of mercury at 250°C. 

The following table gives the vapor pressure of mercury at various temperatures. Fill in the rest of the table, and use the data to plot curves of Pvap versus T and In Pvap versus 1/T. ... 

Since Kp is defined in units of atmospheres, the vapor pressure of mercury at 25°C is 2.6 X 1CT6 atm (0.0020 mm Hg). Because the vapor pressure is appreciable and mercury is toxic in the lungs, mercury should not be handled without adequate ventilation. 

Standard emf Values for the Cell H2/HCl/AgCl, Ag in Various Aqueous Solutions of Organic Solvents at Various Temperatures Temperature Dependence of the Standard Potential of the Silver Chloride Electrode Standard Electrode Potentials of Electrodes of the First Kind Standard Electrode Potentials of Electrodes of the Second Kind Polarographic Half-Wave Potentials (E1/2) of Inorganic Cations Polarographic E1/2 Ranges (in V vs. SCE) for the Reduction of Benzene Derivatives Vapor Pressure of Mercury... 

The following table provides data on the vapor pressure of mercury, useful for assessing and controlling the hazards associated with use of mercury as an electrode.1... 

A quantity of gas is collected in a graduated tube over mercury. The volume of gas at 20°C is 50.0 cm3, and the level of the mercury in the tube is 200 mm above the outside mercury level (see Fig. 5-7). The barometer reads 750 torr. Find the volume at S.T.P. The vapor pressure of mercury is not significant at this... 

Mercury diffusion pumps may be used in the lab to produce a high vacuum. Cold traps are generally placed between the pump and the system to be evacuated. The traps cause the condensation of mercury vapor, which prevents diffusion back into the system. The maximum pressure of mercury that can exist in the system is the vapor pressure of mercury at the temperature of the cold trap. Calculate the number of... 

By using Suprasil quartz envelopes, the radiant power efficiency in the UV-C region of MP mercury lamps can be shifted down to the near VUV region with an increase in efficiency of up to a total of 20% (Fig. 4-3). This effect is dependent on the specific operating conditions of the lamp, i.e. on the transmission characteristics of Suprasil quartz at elevated temperatures and on the vapor pressure of mercury (Lambrecht, 1999). Some companies claim that they have advanced MP Hg lamps available with electric-to-photon energy efficiencies of about 30% in the wavelength range AX of 200 to 300 nm and with power densities of up to 250 Wcm (cf Bolton et al., 1995). 

Two very different kinds of pump fluids have been employed in diffusion pumps. For many years, mercuiy diffusion pumps, were used in small laboratory-bench glass vacuum systems. Mercury pumps are now seldom used owing to the health hazards associated with mercury and the high probability of contamination of the vacuum system with mercury unless a cold trap is used (the vapor pressure of mercury at room temperature is —1.5 mTorr). The oil diffusion pump eliminates the safety hazard and can serve for both small glass and larger metal vacuum systems. 

The following data were obtained in a study of the vapor pressure of mercury (pi) in equilibrium with bismuth amalgams at 321° C ... 

The vapor pressures of mercury in equilibrium with thallium amalgams containing various mole fractions (Ni) of mercury at 26 C were found to be as follows [Hirst and Olson, J. Am. Chem. Soc.y 51, 2398 (1929)] ... 

Boiling mercury is often used in diffusion pumps to attain a very high vacuum pressures down to 10 atm can be readily attained with such a system. Mercury vapor is very toxic to inhale, however. The normal boiling point of Uquid mercury is 3 57°C. What would be the vapor pressure of mercury at 25°C ... 

When a gas is collected over mercury, it is not necessary to make a correction for the vapor pressure of mercury, which is negligible at ordinary temperatures. 

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