Final answer:
In the given reaction, as the temperature increases, the equilibrium constant decreases because the reaction is exothermic. The Si:O ratio in silicate subgroups fluctuates depending on their structure, with quartz having a 1:2 ratio.
Step-by-step explanation:
When considering the reaction 2SO2(g) + O2(g) = 2SO3(g), the equilibrium constant changes as the temperature changes. This is due to Le Châtelier's Principle, which states that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract the change. Since the formation of SO3 is an exothermic reaction, increasing the temperature will shift the equilibrium to the left (towards the reactants), according to the principle. Therefore, as the temperature increases, the equilibrium constant for the forward reaction will decrease.
The Si:O ratio in various silicate subgroups fluctuates depending on the structure of the silicate. For instance, in the mineral quartz, which is composed of silicon dioxide (SiO2), the ratio is 1:2. However, other silicates can have different Si:O ratios due to their varied structures and the presence of other cations.