How many grams of sodium are contained in 0.255 mol of na?

Ineed with a, b, c, d, and e on the long answer

What is impossible to do with a hypothesis

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?