Question

Liquid hexane reacts with gaseous oxygen gas to produce gaseous carbon dioxide and gaseous water . What is the theoretical yield of water formed from the reaction of of hexane and of oxygen gas

Answer 1

`m_(H_2O)=6.84gH_2O`

Step-by-step explanation:

Hello.

In this case, for 5.17 g of hexane (molar mass = 86 g/mol) and 16.5 g of oxygen (molar mass =32 g/mol), we have the reaction:

`C_6H_(14)+(19)/(2) O_2\rightarrow 6CO_2+7H_2O`

Next, via the 1:7 mole ratio of hexane to carbon dioxide and 19/2:7 mole ratio of oxygen to carbon dioxide, we compute the yielded mass of water (molar mass = 18 g/mol) as its theoretical yield by the two masses of reactants and we infer that the limiting reactant is that yielding the fewest moles of product:

`m_(H_2O)^(by\ Hexane)=5.17gC_6H_(12)*(1molC_6H_(12))/(86 gC_6H_(12)) *(7molH_2O)/(1molC_6H_(12))*(18gH_2O)/(1molH_2O) =7.57gH_2O\\\\m_(H_2O)^(by\ Oxygen)=16.5gO_2*(1molO_2)/(32gO_2) *(7molH_2O)/((19)/(2)molO_2 )*(18gH_2O)/(1molH_2O) =6.84gH_2O`

Whereas it is evidenced that oxygen yields the fewest grams of water, therefore, it is the limiting reactant and the theoretical yield of water is:

`m_(H_2O)=6.84gH_2O`

Best regards!