Answer:
You will find the mass of the pan and water but if the water got to its boiling temperature that mass may be a little bit off seeing as some of it may have evaporated
Convert mole to gram by multiplying the molar mass of sodium
0.500mol Na x 22.990g = 11.495g of Na
Organic elements, depends on the context of the question but I suspect that is the answer. The organic elements are H,O,C,N,P,S