How much energy is released when 2.55 kg of diethyl ether freezes?
Amount of diethyl ether((C2H5)2O)= 2.55 Kg
Energy released when 2.55 kg of diethyl ether freezes = ?
Heat must be removed from the (C2H5)2O to cause it to freeze.
The amount of heat released by freezing 1 mole of water is 7.27 kJ/mol.
Formula to calculate the heat required :
q = mHf
where, q = heat in kJ,
m = mass(in grams),
Hf = heat of fusion
We have Hf in terms of moles, but the mass is given in Kg. So let’s convert the mass in Kg to g and then find the number of moles for the given amount of (C2H5)2O.
First, let’s convert mass in Kg to g :
1 kg = 1000g.
Therefore, 2.55 Kg in g will be :
= 2.55 kg
= 2550 g.
Now, let’s find number of moles :
Number of moles(m) =
Molar mass of (C2H5)2O = 74.12 g/mol
Therefore, number of moles =
= 34.40 moles.
So, number of moles in 2550 g of (C2H5)2O is 34.40 moles.