2. How many moles of H2 are needed to produce 36 moles of PH3?

P4 + 6H2 → 4PH3

54 moles

Explanation:

The balanced equation for the reaction is given below:

P4 + 6H2 → 4PH3

From the balanced equation above,

6 moles of H2 are needed to produce 4 moles of PH3.

Therefore, Xmol of H2 will be needed to produce 36 moles of PH3 i.e

Xmol of H2 = (6x36)/4

Xmol of H2 = 54 moles

Therefore, 54 moles of H2 are needed to produce 36 moles of PH3