What is the half-life of the fictitious radioisotope"pennium"?

How many moles of air are there in a human lung with a volume of 2.4 l at stp? explain your answer

There are 6.022, 104 atoms of hg in 1 mole of hg the number of atoms in 45 moles of hg can be found by multiplying 4.5 by 6.022, 102 which is the number of atoms in 4.5 moles of hg, correctly written in scientific notation with the correct number of significant figures? 0 21,109 0 21,100 271, 1024 27.099, 100 mark this and retum save and exit submit

How do you identify the anode on a power source such as a battery? how do you identify the cathode? how are terms anion and cation?