1. For each of the following reactions you want to get more products, however the only thing you can control on your reaction vessel is the volume. Choose if you would increase or decrease the volume to get more product. (Or chose I can't if you don't think you can get more product by changing the volume).

Question

N2(g) + 3H2(g) ==> 2NH3(g) and the options are: I can't, decrease increase
CaCO3(s) <==> CaO(s) + CO2(g) same options
2HF (g) <==> H2(g) + F(2) same options
What i want to know how to solve these types of problems and how volume affects.

Answer 1

Decreasing volume shifts to side with fewer mols. Increasing volume shifts to the side with more moles. Here is some reading mat
https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Equilibria/Chemical_Equilibria/Calculating_An_Equilibrium_Concentrations/Effect_Of_Volume_Changes_On_Gas-phase_Equilibria
For example,
N2(g) + 3H2(g) ==> 2NH3(g) has fewer moles on the right. If you want more NH3 to be produced you decrease the volume.