2NaClO₃ → 2NaCl + 3O₂
mole ratio of NaClO₃ to O₂ is 2 : 3
∴ if moles of NaClO₃ = 12 mol
then moles of O₂ =
= 18 mol
Mass of O₂ = mol of O₂ × molar mass of O₂
= 18 mol × 16 g/mol
= 288 g
So I wasn't sure which equation to use since you did not specify so I just used the decomposition reaction. If you should have used another reaction then just follow the same steps and you'll get your answer.
32 grams of sulfur will contain 6.022 X 1023 sulfur atoms.
C₆H₆ is benzene which has a molar mass of 78 g/mol. When benzene is burned, the reaction is called combustion. The heat produced in this reaction is called the heat of combustion. For benzene, the heat of combustion is -3271 kJ/mol.
Heat of benzene = (8.7 g)(1 mol/78 g)(-3271 kJ/mol) = -364.84 kJ
By conservation of energy,
Heat of benzene = - Heat of water
where
Heat of Water = mCp(Tf - T₀)
where Cp for water is 4.187 kJ/kg·°C
Thus,
-364.84 kJ = -(5691 g)(1 kg/1000 g)(4.187 kJ/kg·°C)(Tf - 21)
<em>Tf = 36.31°C</em>