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479,564.88J of energy is absorbed when what mass of water boils at 100º C?

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Final answer:

To determine the mass of water that boils at 100ºC and absorbs 479,564.88J of energy, we use the equation Q = mLv and calculate the mass using the given latent heat of vaporization of water. The mass of water is approximately 211.858 grams.

Step-by-step explanation:

To calculate the mass of water that boils at 100ºC and absorbs 479,564.88J of energy, we can use the specific heat capacity equation:

Q = mcΔT

Given:
Q = 479,564.88J
ΔT = 100ºC

Since the water is boiling, we assume there is no change in temperature during the phase change. Therefore, the equation becomes:

Q = mLv

Where Lv is the latent heat of vaporization of water. From the given information, we can find that Lv = 40.7 kJ/mol.

We can convert the given energy to kJ by dividing by 1000:

479,564.88J ÷ 1000 = 479.56488 kJ

Now, we can calculate the mass of water by rearranging the equation:

m = Q ÷ Lv

m = 479.56488 kJ ÷ 40.7 kJ/mol = 11.781 mol

Finally, we can convert the number of moles to grams by multiplying by the molar mass of water:

m = (11.781 mol) × (18 g/mol)

= 211.858 g

Therefore, the mass of water that boils at 100ºC and absorbs 479,564.88J of energy is approximately 211.858 grams.

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