The oval surrounding their name was meant to protect them from evil spirits in life and after death. The cartouche has become a symbol representing good luck and protection from evil. Egyptians believed that one who had their name recorded somewhere would not disappear after death. A cartouche attached to a coffin satisfied this requirement.
A single mole can construct 200 mounds over the course of a winter. (Drawing by Jenifer Rees.) Moles construct two kinds of tunnels: surface tunnels and deep tunnels, or runways. Surface tunnels are located 1 to 4 inches below the surface.
The idea here is that the standard molar enthalpy of combustion, Î´Hâcomb, tells you the enthalpy change associated with the combustion of one mole of a given substance under standard conditions. This tells you that every mole of methane that undergoes combustion under standard conditions gives off 890.8 kJ of heat. All you have to do here is use the molar mass of methane to see how many moles you have in that 50.00 g sample. 50.00gâ1 mole CH416.0425g=3.1167 moles CH4.