If the sealed glass is permeable to sunlight or to transfer of heat will be an open system, but if the sealed glass is a thermic glass and doesn't allow exchange of heat and exchange of solar energy (for example a mirrored glass that reflect the sunlight) and the terrarium is not exchanging energy with the surroundings will be a closed system. It is a question that doesn't specify too many details about the system in the study. It is hard to give a final answer without making some assumptions.
Answer:
The active ingredients in baking soda (NaHCO3) are
and 
when Baking soda reacts with Acetic acid
Molecular equation
NaHCO3(aq) + CH3COOH(aq) → Na(CH3COO)(aq) + CO2(g) +H2O(l)
Ionic equation
→ 
as
is present on both sides so it will cancel out and the net ionic equation will be
→ 
When an electron moves from a higher energy shell to a lower one, energy in the form of light, more specifically a wavelength of a photon is released.
There’s no formula that relates solubility to temperature, but you can look up the solubility constant Ksp of substance given and then take the square root of that to find solubility.