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If 575 grams of frozen ethonal are warmed to the freezing point of ethanol, how much heat is required to melt all of this frozen ethanol, CH3CH2OH, at the freezing point? The molar heat of vaporization of ethanol= 4.95 kj/mol

Please help I dont understand, i'll be grateful to the person who answers :((

Answer 1

Henry Antrim

#6.19*10^4J=61.9kJ#

#DeltaE=L_mDeltan#, where:

#n("CH"_3"CH"_2"OH")=(m("CH"_3"CH"_2"OH"))/(M_r("CH"_3"CH"_2"OH"))=575/46=12.5mol#

#DeltaE=12.5*4.95=61.875kJ=6.19*10^4J#

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Answer 2

Cooper Adams

To calculate the heat required to melt frozen ethanol, we first need to determine the number of moles of ethanol using its molar mass. Ethanol's molar mass is approximately 46.07 g/mol.

( \text{Moles of ethanol} = \frac{\text{Mass of ethanol}}{\text{Molar mass of ethanol}} = \frac{575 \text{ g}}{46.07 \text{ g/mol}} )

Once we have the number of moles of ethanol, we can use the molar heat of vaporization to find the heat required to melt the ethanol:

( \text{Heat required} = \text{Moles of ethanol} \times \text{Molar heat of vaporization} )

( \text{Heat required} = \left( \frac{575 \text{ g}}{46.07 \text{ g/mol}} \right) \times 4.95 \text{ kJ/mol} )

Finally, we can calculate this:

( \text{Heat required} \approx 61.5 \text{ kJ} )

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.