Answer:
![6.8 molH_2O](https://img.qammunity.org/2022/formulas/chemistry/high-school/hjnerilxvfze4210v1coi6jm304l0dw8h3.png)
Step-by-step explanation:
Hello there!
In this case, for this balanced chemical reaction about the combustion of methane, it is possible for us to inspect the 2:2 mole ratio of water to oxygen as given for their coefficients in the balanced chemical reaction.
In such a wat, given 6.8 moles of oxygen, we can easily obtain the produced moles of water by applying the aforementioned mole ratio as shown below:
![6.8molO_2*(2molH_2O)/(2molO_2)\\\\6.8 molH_2O](https://img.qammunity.org/2022/formulas/chemistry/high-school/els90bv4x4fvneydtgfm84cf94cn5fd1wn.png)
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