How many moles are in 3.50 x 1024 atoms of yttrium

Which process does not require the presence of a physical substance in order to transfer heat? air in the atmosphere is heated by the ground. this warm air then rises, and cooler air falls. this is an example of what type of process? how is conduction different from radiation?

Connect the whole numbers on the periodic table to indicate what they represent?

Which factor is likely to impact the possible number of compounds ?