How much heat is needed to melt a 25 gram ice-cube at 0 °C? The molar heat of fusion for water is 6.01 kJ/mol.
A) 6.01 kJ
B) 8.35 kJ
C) 150.25 kJ
D) 3.34 kJ
E) 9.22 kJ
mass ice x heat fusion = q.
To find the amount of heat needed to melt the ice cube, we can use the formula:
Q = n * ∆H
Where Q is the heat, n is the number of moles of ice, and ∆H is the molar heat of fusion.
First, we need to calculate the number of moles of ice. We can use the molar mass of water to do this:
molar mass of water = 18.02 g/mol
n = mass / molar mass
n = 25 g / 18.02 g/mol ≈ 1.387 mol
Now we have the number of moles of ice. Substituting the values in the formula:
Q = 1.387 mol * 6.01 kJ/mol
Q ≈ 8.33787 kJ
Rounding the answer to two decimal places, we get:
Q ≈ 8.34 kJ
Therefore, the amount of heat needed to melt the 25 gram ice cube at 0 °C is approximately 8.34 kJ.
The correct answer is (D) 3.34 kJ.