Answer:
number of moles = 6.393 moles
Explanation:
One mole of any substance contains Avogadro's number (6.022 * 10^23) of atoms.
Therefore, to know the number of moles that contain 3.85 * 10^24 atoms, all we have to do is cross multiplication as follows:
1 mole ......................> 6.022 * 10^23
?? moles ..................> 3.85 * 10^24
number of moles = (3.85 * 10^24 *1) / (6.022 * 10^23)
number of moles = 6.393 moles
Hope this helps :)
Answer:
The volume of the gas will be 78.31 L at 1.7 °C.
Explanation:
We can find the temperature of the gas by the ideal gas law equation:
Where:
n: is the number of moles
V: is the volume
T: is the temperature
R: is the gas constant = 0.082 L*atm/(K*mol)
From the initial we can find the number of moles:
Now, we can find the temperature with the final conditions:
The temperature in Celsius is:
Therefore, the volume of the gas will be 78.31 L at 1.7 °C.
I hope it helps you!
Answer:
84.24 g
Explanation:
Given data:
Mass of oxygen = 75 g
Mass of Al required to react = ?
Solution:
Chemical equation:
4Al + 3O₂ → 2Al₂O₃
Number of moles of oxygen:
Number of moles = mass/ molar mass
Number of moles = 75 g/ 32 g/mol
Number of moles = 2.34 mol
Now we will compare the moles of oxygen with Al.
O₂ : Al
3 : 4
2.34 : 4/3×2.34 = 3.12 mol
Mass of Al required:
Mass = number of moles × molar mass
Mass = 3.12 mol × 27 g/mol
Mass = 84.24 g
Answer:
No, it is not sufficient
Please find the workings below
Explanation:
Using E = hf
Where;
E = energy of a photon (J)
h = Planck's constant (6.626 × 10^-34 J/s)
f = frequency
However, λ = v/f
f = v/λ
Where; λ = wavelength of light = 325nm = 325 × 10^-9m
v = speed of light (3 × 10^8 m/s)
Hence, E = hv/λ
E = 6.626 × 10^-34 × 3 × 10^8 ÷ 325 × 10^-9
E = 19.878 × 10^-26 ÷ 325 × 10^-9
E = 19.878/325 × 10^ (-26+9)
E = 0.061 × 10^-17
E = 6.1 × 10^-19J
Next, we work out the energy required to dissociate 1 mole of N=N. Since the bond energy is 418 kJ/mol.
E = 418 × 10³ ÷ 6.022 × 10^23
E = 69.412 × 10^(3-23)
E = 69.412 × 10^-20
E = 6.9412 × 10^-19J
6.9412 × 10^-19J is required to break one mole of N=N bond.
Based on the workings above, the photon, which has an energy of 6.1 × 10^-19J is not sufficient to break a N=N bond that has an energy of 6.9412 × 10^-19J
or simply 2,8 it is isoelectronic with argon
