A manometer attached to a flask contains ammonia gas have no difference in mercury level initially as shown in diagram. After sparking into the flask, ammonia is partially dissociatedas `2NH_(3)(g) to N_(2)(g)+3H_(2)(g)` now it have difference of 6 cm in mercury level in two columns, what is partial pressure of `H_(2)(g)` at equilibrium?

Options

A. 9 cm Hg
B. 18 cm Hg
C. 27 cm Hg
D. 15 cm Hg

Answer

A

Explanation

`{:(2 NH_(3) (g) to N_(2) (g) + 3H_(2) (g)), (76 " " 0 " " 0) , (76-2x " " x " " 2x):}` before sparking
After sparking at eqm
Partial pressure of `H_(2) = 3 xx 3 = 9` cm Hg