How many grams of oxygen are required to combine with 0.750 grams of nitrogen in the compound: N2O5?

2.14 g.

Explanation:

Hello!

In this case, since the mole ratio between nitrogen and oxygen is 2:5 respectively, we realize we first need the moles of nitrogen given it's atomic mass (14.01 g/mol):

Now, we calculate the moles of oxygen:

Then, we compute the moles of oxygen given its atomic mass (16.00 g/mol):

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the temperature of the gas, in k, not celsius.