For the following endothermic reaction system at equilibrium:

2SO3(g) 2SO2(g) O2(g)

Choose the changes that will shift the equilibrium position to the right. (Select all that apply.)

a. Decrease temperature
b. Add Ne(g)
c. Add a catalyst
d. Remove SO3(g)
e. Add SO2(g)
f. Decrease volume
g. Increase temperature

The correct answer is g. Increase temperature

Explanation:

We have the following endothermic reaction at equilibrium:

2 SO₃(g) ⇄ 2 SO₂(g) + O₂(g)

According to the Le Chatelier's principle, if certain conditions of a reaction at equilibrium are changed, the system will try to contrarrest the effect of the change. The factors that can modify the equilibrium position are: concentration of reactant of products, temperature, volume and pressure (for a reaction in gas phase).

In this reaction, the changes that will shift the equilibrium position to the right (towards the formation of products) will be: the decrease in products (SO₂ or O₂), the addition of reactant (SO₃), the decrease of pressure or the increase in volume (because reactants and products are in gas phase) and the increase of temperature (because it is an endothermic reaction, so it requires heat). Remember that the presence of catalyst does not modify the equilibrium position because the catalyst accelerates the reaction by reducing the activation energy (So, the option c is not correct).

The decrease of volume will not change the equilibrium position to the right. That is because as the volume decreases, the total pressure of the gas system increases. So, the equilibrium would shift towards the direction of decreased pressure (that is, towards the formation of the lesser number of gas moles). So, the equilibrium will shift towards the left (2 moles).

From the options, the only which is correct is option g (increase temperature).

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people were used to cutting slices as they needed them and storing bread in a specially-made wooden or metal breadbox or pail with a lid to preserve it longer, but the first automatically sliced commercial loaves were produced on july 6, 1928, in chillicothe, missouri, using a machine invented by otto rohwedder, an iowa-born, missouri-based jeweler.[1] pre-sliced bread would indeed dry out, were it not for another 20th century technology: the plastic bag. bread could now be pre-sliced, and if the enclosing bag remains sealed as much as possible, the bread will remain soft and fresh for longer than if sitting unwrapped on a shelf or enclosed in a bread box that is not air-tight. sealed packaging meant bread could also be sold on store shelves and eliminate frequent trips to a bakery.

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the cold front replaces the warmer air at the ground level changing the wind to be breezy and denser.there is also an immediate drop in the temperature.