Answer:
The coefficient for PH3 is 8. Option D is correct.
Explanation:
Step 1: The unbalanced equation
P2H4(g) ⇆ PH3(g) + P4(s)
Step 2: Balancing the equation
P2H4(g) ⇆ PH3(g) + P4(s)
On the left side we have 4x H (in P2H4), on the right side we have 3x H (in PH3). To balance the amount of H on both sides, we have to multiply P2H4 on the left side by 3 and PH3 on the right by 4.
3P2H4(g ) ⇆ 4PH3(g) + P4(s)
On the left side we have 6x P (in 3P2H4) on the right side we have 8x P (4x in 4PH3 and 4x in P4). To balance the amount of P on bot hsides, we have to multiply 3P2H4 by 2 and 4PH3 also by 2. Now the equation is balanced
6P2H4(g ) ⇆ 8PH3(g) + P4(s)
The coefficient for PH3 is 8. Option D is correct.