If 50% of radioactive element remains after 4000 years what what is the half life

Mercury turns to vapor at 629.88 k how much heat is lost 175 g of mercury vapor at 650 current condenses to a liquid at 297 ca mercury turns to weber at 629.88 kelvin how much he is lost 175 g of mercury vapor and 650 coming condensers to liquidate 297 kevin

Liquid ammonia is produced at high temperatures and under great pressure in a tank by passing a mixture of nitrogen gas and hydrogen gas over an iron catalyst. the reaction is represented by the following equation. n2(g) + 3h2(g) → 2nh3(g) changing all but one experimental condition will affect the amount of ammonia produced. that condition is a) increasing the concentration of both reactants b) changing the temperature within the tank c) decreasing the pressure within the tank. d) increasing only the amount of nitrogen present.

Determine the ph of 0.10 m nh3 solution. nh3 is a weak base with a kb equal to 1.8 x 10-5 round answer to nearest whole number.