Answer:
Explanation:
When the volume and temperature of a gas are unchanged, the pressure is directly related to the number of molecules, this is:
[tex]p=Kn[/tex]
Or:
[tex]\dfrac{p_1}{n_1}=\dfrac{p_2}{n_2}[/tex]
Thus:
[tex]p_2=p_1\times \dfrac{n_2}{n_1}[/tex]
For the reaction 3A(g) → 2B(g), n₁ = 3 and n₂ = 2.
Then:
[tex]p_2=0.74atm\times \dfrac{2}{3}\approx0.49atm[/tex]
As you see, the pressure decreases, because the number of molecules decreases.