Answer:
0.0826 mol (corrected to 3 sig. fig.)
Explanation:
First, balance the equation:
2NH3 →3H2 + N2
Take the atomic no. of N=14.0, and H=1.0,
no. of moles = mass / molar mass
So, no. of moles of NH3 dissociated = 2.81 / (14.0+1.0x3)
= 0.165294117mol
From the equation, the mole ratio of NH3:N2 = 2:1, meaning for every 2 moles of NH3 dissociated, one mole of N2 is formed.
So, using this ratio, the no. of moles of N2 formed will be 0.165294117 / 2
=0.0826 mol (corrected to 3 sig. fig.)
