How many molecular of H2O and O2 are present in 8.5g of H2O2 ?​

2H2O+O2--->2H2O2  

8.5 gm H2O2=0.25 mole  

hence H2O is also 0.25 mole i.e.4.5 gm  

O2is 0.125 mole i.e.4 gm

geosphere and hydrosphere.

this is because the geosphere has to do with geological events, while the hydrosphere controls all water on earth.

it is the most commonly accepted one