What is the occurrence, ore and uses of Gold, platinum and tantalum​

Fill in the coefficients that will balance the following reaction: a0cr2(so4)3 + a1agno3

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?

What is the number of neutrons in an atom with atomic mass of 35