how do i "verify that for the following reaction to be completed, 4 liters of hydrogen would requite at least 2 liters of oxygen gas at the same pressure and temperature. 2 H2 + O2 --> 2 H2O

Thank you for the opportunity to help you with your question!

on multiplying the equation by a factor 2, we get: 4H2 + 2 O2 --> 4 H2O

Thus we can see that 4 liters of hydrogen would requite at least 2 liters of oxygen gas at the same pressure and temperature.

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