Question

$2HI\left(g\right)\leftrightharpoons H_2\left(g\right)+I_2\left(g\right)$
An increase in pressure in the above reaction would :

• A. produce more $I^{-}\left(aq\right)$
• B. produce more $H_2$
• C. not affect the system
• D. drive it to the right
• E. drive it to the left

Answer 1

Answer: (C)

not affect the system

$2HI\iff H_2+I_2$
2moles 2 moles
$\Delta n_{\left(g\right)}=2-2=0$
In any reaction when the number of gas particles ( molecules) are same in both side ( Left and right side of the reaction equation) then there is no effect of the increase/decrease of the pressure.