Which is the most soluble substance listed

What are the variables in gay-lussac’s law? pressure and volume pressure, temperature, and volume pressure and temperature volume, temperature, and moles of gas

Can someone me with questions 12 and 13 plz.

Which formula can be used to calculate the molar mass of ammonia (nh3)? molar mass of n + molar mass of h 3 × molar mass of n + molar mass of h molar mass of n + 3 × molar mass of h 3 × molar mass of n + 3 × molar mass of h