Answer:

Explanation:
Hello,
In this case, we consider oxygen as an ideal gas, for that reason, we use yhe ideal gas equation to compute the moles based on:

Hence, at 3.50 atm and 25 °C for a volume of 2.00 L we compute the moles considering absolute temperature in Kelvins:

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Answer:
solid change directly into a vapor in the process known simply as freezing
Answer:
1,063 grams H₃PO₄
Explanation:
To find the mass of phosphoric acid (H₃PO₄), you should (1) convert molecules to moles (via Avogadro's number) and then (2) convert moles to grams (via molar mass from periodic table).
Molar Mass (H₃PO₄): 3(1.008 g/mol) + 30.974 g/mol + 4(15.998 g/mol)
Molar Mas (H₃PO₄): 97.99 g/mol
6.534 x 10²⁴ molecules H₃PO₄ 1 mole 97.99 g
--------------------------------------------- x ------------------------------------- x --------------
6.022 x 10²³ molecules 1 mole
= 1,063 grams H₃PO₄