Question

Three moles of $PCl_5$, three moles of $PCl_3$ and two moles of $Cl_2$ are taken in a closed vessel. If at equilibrium the vessel has $1.5$ moles of $PCl_5$, the number of moles of $PCl_3$ present in it is

• A. 5
• B. 3
• C. 6
• D. 4.5

Answer 1

Answer: (D)

4.5

Answer 2

$\therefore\,\,\,\,\, 3-x =1.5$
$x =1.5$

Number of moles of $PCl _{3}=3+x$
$=3+1.5=4.5$