Is CO2 a strong acid, weak acid, strong base, weak base or molecular compound?

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.

What type of reaction fuels the processes seen here?

Which of the following is in the lanthanide family? a) uranium b) promethium c) silver d) gold