Dimensional analysis 9 lemons = 1 orange How many lemons in 10 oranges?

Which of the following observations indicates that there is a small, dense, positively charged part in the center of an atom? some uncharged particles are scattered by a gold foil. all uncharged particles are attracted towards a gold foil. all positively charged particles pass straight through a gold foil. some positively charged particles bounce back from a gold foil.

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

Which compound most likely has the greatest bond energy?