The standard molar heat of vaporization
for water is 40.79 kJ/mol. How
much energy would be required to vaporize
8.51 ×1010 molecules of water?
Answer in units of kJ.
Thanks for the help!!!
How many mols in 8.51E10 molecules?
That's 8.51E10 moleceles x (1 mol molecules/6.02E23 molecules) = ?
Then q in kJ = mols H2O x Hvap(kJ/mol)
6.02*10^23 molecules/mol
so
40.79kJ /6.02*10^23 molecules
times I suspect you mean 8.51*10^10 molecules
40.79 (8.51/6.02)10^(10-23)
57.66 * 10^-13
or
5.766 * 10^-12 kJ
To find the energy required to vaporize 8.51 × 10^10 molecules of water, you should follow these steps:
1. Determine the number of moles of water molecules:
Number of moles = Number of molecules / Avogadro's number
Avogadro's number = 6.022 × 10^23 molecules/mol
Number of moles = (8.51 × 10^10) / (6.022 × 10^23)
Number of moles ≈ 1.412 × 10^(-13) mol
2. Calculate the energy required to vaporize the given number of moles of water molecules:
Energy (kJ) = Number of moles × Standard molar heat of vaporization
Energy (kJ) = (1.412 × 10^(-13)) × 40.79 kJ/mol
3. Solve the equation:
Energy (kJ) ≈ 5.758 × 10^(-12) kJ
Therefore, approximately 5.758 × 10^(-12) kJ of energy would be required to vaporize 8.51 × 10^10 molecules of water.
To find out how much energy is required to vaporize a given number of molecules of water, we need to use the standard molar heat of vaporization (ΔHvap) and Avogadro's number (6.022 × 10^23 molecules/mol).
First, we need to calculate the number of moles of water in 8.51 × 10^10 molecules. To do this, divide the given number of molecules by Avogadro's number:
8.51 × 10^10 molecules / 6.022 × 10^23 molecules/mol ≈ 1.41 × 10^-13 mol
Now, we can use the standard molar heat of vaporization (40.79 kJ/mol) to calculate the energy required to vaporize this amount of water. Multiply the number of moles by the value of the heat of vaporization:
1.41 × 10^-13 mol * 40.79 kJ/mol ≈ 5.74 × 10^-12 kJ
Therefore, approximately 5.74 × 10^-12 kJ of energy would be required to vaporize 8.51 × 10^10 molecules of water.