25.9 kJ/mol. (3 sig. fig. as in the heat capacity.)
<h3>Explanation</h3>
The process:
.
How many moles of this process?
Relative atomic mass from a modern periodic table:
- K: 39.098;
- N: 14.007;
- O: 15.999.
Molar mass of 
:
.
Number of moles of the process = Number of moles of dissolved:
.
What's the enthalpy change of this process?
for 
. By convention, the enthalpy change 
measures the energy change for each mole of a process.
.
The heat capacity is the least accurate number in these calculation. It comes with three significant figures. As a result, round the final result to three significant figures. However, make sure you keep at least one additional figure to minimize the risk of rounding errors during the calculation.
Answer:
Moles of H₂S needed = 6.2 mol
Moles of SO₂ produced = 6.2 mol
Explanation:
Given data:
Number of moles of O₂ = 9.3 mol
Moles of H₂S needed = ?
Moles of SO₂ produced = ?
Solution:
Chemical equation:
2H₂S + 3O₂ → 2SO₂ + 2H₂O
Now we will compare the moles of oxygen with H₂S.
O₂ : H₂S
3 : 2
9.3 : 2/3×9.3 = 6.2 mol
Now we will compare the moles of SO₂ with both reactant.
O₂ : SO₂
3 : 2
9.3 : 2/3×9.3 = 6.2 mol
H₂S : SO₂
2 : 2
6.2 : 6.2 mol
So 6.2 moles of SO₂ are produced.
Molar mass Cu(OH)₂ = 97.561 g/mol
97.561 g Cu(OH)₂ --------------- 6.02x10²³ atoms
? g Cu(OH)₂ -------------------- 9.1x10²⁵ atoms
mass = 9.1x10²⁵ * 97.561 / 6.02x10²³
mass = 8.87x10²⁷ / 6.02x10²³
mass = 14734.2 g
hope this helps!
Answer:
Wind direction is determined with a wind vane.
Hope it will help :)
