They are built from particles and blobs of congealed lava ejected from a single vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as cinders around the vent to form a circular or oval cone, making them the simplest out there
Molar mass of sodium=23g 2 mole sodium gives 2 g H2 i.e 46g sodium gives 2g H2 so 65.4g will give=2.84g H2 now no. of molecules = 2.8/2*avogadros number
