Consider a rod placed vertically into the ground with exactly one meter above the ground sticking up. assume you are someplace like bonneville, ut (famous for auto racing) where the earth will be assumed perfectly level and smooth without hills or valleys or trees to worry about. how far must the stick be from you so that it becomes invisible from a vantage point of being on the ground (face or eyeball at ground level as if you're an ant)? consider the curvature of the earth in this case. earth's radius is 6.37 * 10^6 m. do the calculation again for an eyeball height of 1.5m above the ground.

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂

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