<span>12.4 g
First, calculate the molar masses by looking up the atomic weights of all involved elements.
Atomic weight manganese = 54.938044
Atomic weight oxygen = 15.999
Atomic weight aluminium = 26.981539
Molar mass MnO2 = 54.938044 + 2 * 15.999 = 86.936044 g/mol
Now determine the number of moles of MnO2 we have
30.0 g / 86.936044 g/mol = 0.345081265 mol
Looking at the balanced equation
3MnO2+4Al→3Mn+2Al2O3
it's obvious that for every 3 moles of MnO2, it takes 4 moles of Al. So
0.345081265 mol / 3 * 4 = 0.460108353 mol
So we need 0.460108353 moles of Al to perform the reaction. Now multiply by the atomic weight of aluminum.
0.460108353 mol * 26.981539 g/mol = 12.41443146 g
Finally, round to 3 significant figures, giving 12.4 g</span>
Answer:
it would be the second one thank me later
Explanation:
Answer:According to Boyle's Law, the volume of a gas is inversely proportional to the pressure of a gas. Therefore, increasing the volume has the same effect as decreasing the pressure. If the volume in which a gas reaction takes place is DECREASED, the reaction will shift toward the side with fewer moles of GAS.
Explanation:
Answer:
A concentrated solution is one that has a relatively large amount of dissolved solute. A dilute solution is one that has a relatively small amount of dissolved solute.
Answer:
0.013%
Yes, it does. The answer agrees with the statement.
Explanation:
Both conformers are in equilibrium, and it can be represented by the equilibrium equation K:
K = [twist-boat]/[chair]
The free energy between them can be calculated by:
ΔG° = -RTlnK
Where R is the gas constant (8.314 J/mol.K), and T is the temperature (25°C + 273 = 298 K).
ΔG° = 5.3 kcal/mol * 4.182 kJ/kcal = 22.165 kJ/mol = 22165 J/mol
22165 = -8.314*298*lnK
-2477.572lnK = 22165
lnK = -8.946
K = 
K = 1.30x10⁻⁴
[twist-boat]/[chair] = 1.30x10⁻⁴
[twist-boat] = 1.30x10⁻⁴[chair]
The percentage of the twist-boat conformer is:
[twist-boat]/([twist-boat] + [chair]) * 100%
1.30x10⁻⁴[chair]/(1.30x10⁻⁴[chair] + [chair]) *100%
0.013%
The statement about the conformers is that the chair conformer is more stable, and because of that is more present. So, the answer agrees with it.
