Is volume one of your answers?
Mass C₆H₈O₇ : 0.531484 g
<h3>Further explanation</h3>
Reaction
3NaHCO₃ (aq) + C₆H₈O₇ (aq) → 3 CO₂ (g) + 3 H₂O (l) + Na₃C₆H₅O₇ (aq)
MW NaHCO₃ : 84 g/mol
mass NaHCO₃ : 7.10² mg=0.7 g
mol NaHCO₃ :

mol C₆H₈O₇ :

MW C₆H₈O₇ : 192 g/mol
mass C₆H₈O₇ :

So, you need to have same ammount of atoms on the left and on the right side of the equation. You need to count the ammount of attoms of every substance on the left, and make sure that on the right side the ammount is same. For example in the 1st one it’s 6Sn+2P4=2Sn3P4, so that you have 6atoms of Sn on the left and 6 atoms of Sn on the right, same with the P
Answer: option A. 350 K and 0.30 atm
Explanation: a gas behaves as an ideal gas at higher temperature and low pressure