Answer: 46.6 grams
Explanation:
[tex]2C_6H_{14}+19O_2\rightarrow 12CO_2+14H_2O[/tex]
Given : density of hexane = 0.660 g/ml
volume of hexane = 20 ml
Mass of hexane = [tex]{\text {density of hexane}}\times {\text {volume of hexane}}=0.660g/ml\times 20ml=13.2g[/tex]
moles of hexane =[tex]\frac{\text {given mass}}\times {\text {molar mass}}=\frac{13.2g}{86.18g/mol}=0.15moles[/tex]
According to stoichiometry :
2 moles of hexane reacts with 19 moles of oxygen
Thus 0.14 moles hexane will react with =[tex]\frac{19}{2}\times 0.15=1.45[/tex] moles of oxygen
Mass of oxygen =[tex]moles\times {\text {molar mass}}=1.45\times 32=46.6g[/tex]
Thus minimum mass of oxygen required for the complete reaction of 20.0 mL of hexane is 46.6 grams.
