How did qualitative chemical and enzyme tests avery identify dna as the transforming principle?

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )

Chlorine and water react to form hydrogen chloride and oxygen, like this: 2cl2 (g) + 2h2o (g) → 4hcl (g) + o2 (g) also, a chemist finds that at a certain temperature the equilibrium mixture of chlorine, water, hydrogen chloride, and oxygen has the following composition: compound concentration at equilibrium cl2 0.55m h2o 0.57m hcl 0.53m o2 0.34m calculate the value of the equilibrium constant kc for this reaction. round your answer to 2 significant digits.

Ahelium balloon contains 16.9 l of helium at stp. how many atoms of helium are in the balloon