What is the heaviest natural element?​

At 20°c, a sample of h2o liquid and a sample of co2 gas each have the same average kinetic energy. why is one a liquid and the other a gas at this temperature?

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

Sum of brother and sisters age is 26. four times the brothers age is subtracted from three times the sisters age, the difference is 8. what are the ages of the brother and sister?