Answer:
Water gradually degrades them until the metal parts rust and the other materials deteriorate.
Explanation:
Hydrochloric acid and sodium hydroxide
HCl + NaOh ----> NaCl + H2O
They become more stable because they achieve a full outer shell of valence electrons with the magic number of 8.
The ideal gas under STP is 22.4 L/mol. While the gas has a rule of P1V1/T1=P2V2/T2. So the volume under 101 kPa and 273 K is 0.2*22.4=4.48 L.