How many grams of oxygen will react completely with a block of calcium metal that is 3.0 cm by 3.5 cm by 4.2 cm, if the density of calcium is 1.55 g/ml? show all steps of your calculations as well as the final answer. ca + o2 > cao its a response question

Volume of Ca =  3.0 cm × 3.5 cm × 4.2 cm
                        = 44.1 cm³  = 44.1 mL

          Mass = volume × density
Mass of Ca = 44.1 mL × 1.55 g/mL
                    = 68.355 g

Now, since moles =  mass ÷ molar mass
 then moles of Ca = 68.355 g ÷ 40 g/mol
                               = 1.7089 mol

The balanced equation for the reaction between Ca and O₂ :
                        2 Ca   +   O₂  →  2 CaO

     the mole ratio of Ca  :  O₂  is  2  :  1
(which means that there are two times more moles of Ca than moles of O₂)

∴ if moles of Ca = 1.7089 mol

then moles of O₂ = 1.7089 mol  ÷ 2
                              =  0.8545 mol

Now,      mass  = moles × molar mass

      ⇒  mass of O₂ = 0.8545 mol × 32 g/mol
                              = 27.34 g

∴ the grams of oxygen will react completely with a block of calcium metal is 27.34 g