Answer:
The maximum mass of sodium sulfide that could be produced is 35.26 grams.
Explanation:
Moles of sodium sulfate =
Moles of carbon =
According to reaction, 1 mole of sodium sulfate reacts with 4 moles of carbon.
Then 0.6514 moles of sodium sulfate will react with:
of carbon.
2.6056 moles of carbon > 1.8083 mol of carbon (given)
As we can see that moles of sodium sulfate are in excess ,so, the amount of sodium sulfide will depend upon moles of carbon.
According to reaction, 4 mole of carbon gives with 1 moles of sodium sulfide.
Then 1.8083 moles of carbon will give :
of sodium sulfide.
Mass of 0.4521 moles of sodium sulfide:
0.4521 mol × 78 g/mol = 35.26 g
The maximum mass of sodium sulfide that could be produced is 35.26 grams.
This problem uses the relationship between Kb and the the dissociation constants which is expressed as Kw = KaKb. Calculations are as follows:
<span>
Kb = KaKb
</span><span>1.00 x 10^-14 = 7.2 x 10^-4(x)
</span><span>x = 1.39 x 10^-11
</span><span>
We now need to calculate the [OH¯] using the Kb expression:
</span>1.39 x 10^-11 = x^2 / (0.30 - x)
<span>
The denominator can be neglected. </span><span>Thus, x is 3.73 x 10^-6.
</span><span>
pOH = -log 3.73 x 10^-6 = 5.43
p</span><span>H = 14-5.43 = 8.57</span>
Answer:
Mass = 17.12 g
Explanation:
Given data:
Mass of Al = 3.90 g
Mass of H₂SO₄ = 13.65
Mass of aluminium sulfate = ?
Solution:
Chemical equation:
3H₂SO₄ + 2Al → Al₂(SO₄)₃ + 3H₂
Now we will calculate the number of moles of each reactant.
Moles of H₂SO₄:
Number of moles = mass/ molar mass
Number of moles = 13.65 g/ 98.079 g/mol
Number of moles = 0.14 mol
Moles of Al:
Number of moles = mass/ molar mass
Number of moles = 3.90 g/ 27 g/mol
Number of moles = 0.14 mol
Now we will compare the moles of aluminium sulfate with sulfuric acid and aluminium.
H₂SO₄ : Al₂(SO₄)₃
3 : 1
0.14 : 1/3×0.14 = 0.05
Al : Al₂(SO₄)₃
2 : 1
0.14 : 1/2×0.14 = 0.07
The number of moles of aluminium sulfate produced by sulfuric acid are less so it will limiting reactant and limit the amount of aluminium sulfate.
Mass of aluminium sulfate:
Mass = number of moles × molar mass
Mass = 0.05 mol × 342.15 g/mol
Mass = 17.12 g