Question

When hydroge sulfide gas is passed through a solution of lead (II) nitrate, lead (II) sulfide precipitates out. Write a balanced equation for this reaction and calculate an average rate, in mol/s for the reaction from this data:

1) at 0 seconds, mass of lead (II) sulide is 0 g
2) at 5 seconds, mass is 2.8 g
3) at 10 seconds, mass is 6.1 g
4) at 15 seconds, mass is 9 g
5) at 20 seconds, mass is 11.7 g

(molar mass of lead (II) sulfide is 239.27)

Answer 1

I would average the five runs to give g/s, then divide by 239.27 to change to moles/s.

Answer 2

H2s + Pb(NO3)2 : 2HNO3 + PbS
But i am not sure of the average rate , can you please tell me the answer?