How many moles of o2 are required to generate 18 moles of h2o in the given reaction? 2c8h18 + 25o2 16co2 + 18h2o

There's a slight error in your equation. I think you were trying to present it like this:

2C8H18 + 25O2 -> 16CO2 + 18H2O

Mole Ratio
O2 : H20
25 : 18
? moles : 18 moles
(18/18)×25 : 18 moles

25 moles : 18 moles

Final answer would be 25 moles of O2. :)

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It is a mixture. simply put, a compound must be pure, that is, of only one chemical structure and composition. a mixture is made of different chemical substances (i.e. elements, molecules, compounds) that are not chemically bonded to each other, but instead physically grouped together, as in the case of gasoline (a homogeneous solution).

The answer to your q it is d