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)

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

H2s + Pb(NO3)2 : 2HNO3 + PbS

But i am not sure of the average rate , can you please tell me the answer?

The balanced equation for the reaction between hydrogen sulfide gas and lead (II) nitrate can be written as:

Pb(NO3)2 + H2S -> PbS + 2HNO3

To calculate the average rate of the reaction, we need to determine the change in the mass of lead (II) sulfide over a given time period.

Using the given data:
1) At 0 seconds, the mass of lead (II) sulfide is 0 g.
2) At 5 seconds, the mass is 2.8 g.
3) At 10 seconds, the mass is 6.1 g.
4) At 15 seconds, the mass is 9 g.
5) At 20 seconds, the mass is 11.7 g.

Let's find the change in mass for each time interval:

Mass change from 0 seconds to 5 seconds: 2.8 g - 0 g = 2.8 g

Mass change from 5 seconds to 10 seconds: 6.1 g - 2.8 g = 3.3 g

Mass change from 10 seconds to 15 seconds: 9 g - 6.1 g = 2.9 g

Mass change from 15 seconds to 20 seconds: 11.7 g - 9 g = 2.7 g

Now, let's calculate the average rate for each time interval:

Average rate from 0 to 5 seconds: (2.8 g) / (5 s - 0 s) = 0.56 g/s

Average rate from 5 to 10 seconds: (3.3 g) / (10 s - 5 s) = 0.66 g/s

Average rate from 10 to 15 seconds: (2.9 g) / (15 s - 10 s) = 0.58 g/s

Average rate from 15 to 20 seconds: (2.7 g) / (20 s - 15 s) = 0.54 g/s

Therefore, the average rates (in mol/s) for the reaction are approximately:
0.56 g/s = 0.00234 mol/s
0.66 g/s = 0.00276 mol/s
0.58 g/s = 0.00243 mol/s
0.54 g/s = 0.00226 mol/s

Please note that the molar mass of lead (II) sulfide (PbS) is needed to convert grams to moles. The given molar mass of 239.27 g/mol is not relevant for the calculation of average rates.

To write a balanced equation for the reaction between hydroge sulfide gas and lead (II) nitrate, we first identify the reactants and the products. From the problem statement, the reactants are hydrogen sulfide (H2S) and lead (II) nitrate (Pb(NO3)2). The product is lead (II) sulfide (PbS).

The balanced equation for the reaction can be written as follows:
H2S + Pb(NO3)2 -> PbS + 2HNO3

To calculate the average rate of the reaction, we can use the formula:
Rate = (Change in mass of PbS) / (Change in time)

Given the following mass values at different time intervals:
- At 0 seconds, mass of PbS = 0 g
- At 5 seconds, mass of PbS = 2.8 g
- At 10 seconds, mass of PbS = 6.1 g
- At 15 seconds, mass of PbS = 9 g
- At 20 seconds, mass of PbS = 11.7 g

We can calculate the change in mass of PbS at each time interval:
- Change in mass from 0 to 5 seconds: 2.8 g - 0 g = 2.8 g
- Change in mass from 5 to 10 seconds: 6.1 g - 2.8 g = 3.3 g
- Change in mass from 10 to 15 seconds: 9 g - 6.1 g = 2.9 g
- Change in mass from 15 to 20 seconds: 11.7 g - 9 g = 2.7 g

Next, we can calculate the change in time between each interval:
- Change in time from 0 to 5 seconds: 5 s - 0 s = 5 s
- Change in time from 5 to 10 seconds: 10 s - 5 s = 5 s
- Change in time from 10 to 15 seconds: 15 s - 10 s = 5 s
- Change in time from 15 to 20 seconds: 20 s - 15 s = 5 s

Finally, we can calculate the average rate using the formula mentioned earlier:
- Average rate from 0 to 5 seconds: (2.8 g - 0 g) / (5 s - 0 s) = 0.56 g/s
- Average rate from 5 to 10 seconds: (3.3 g - 2.8 g) / (5 s - 0 s) = 0.1 g/s
- Average rate from 10 to 15 seconds: (2.9 g - 0 g) / (10 s - 5 s) = 0.58 g/s
- Average rate from 15 to 20 seconds: (2.7 g - 0 g) / (15 s - 10 s) = 0.54 g/s

Therefore, the average rates for the reaction at different time intervals are approximately:
- 0 to 5 seconds: 0.56 g/s
- 5 to 10 seconds: 0.1 g/s
- 10 to 15 seconds: 0.58 g/s
- 15 to 20 seconds: 0.54 g/s