To calculate the amount of heat needed to melt 35.0 g of ice at 0 °C, we can use the formula:
Q = m * ΔH_fus
where Q is the amount of heat, m is the mass of the substance being melted (in grams), and ΔH_fus is the heat of fusion, which is the amount of heat needed to melt one gram of the substance.
For water, ΔH_fus is 6.01 kJ/mol, or 334 J/g.
First, we need to convert the mass of ice from grams to moles. The molar mass of water is 18.015 g/mol, so:
moles of ice = 35.0 g / 18.015 g/mol = 1.943 mol
Now we can calculate the amount of heat needed:
Q = m * ΔH_fus
Q = 35.0 g * 334 J/g
Q = 11,690 J
Therefore, the amount of heat needed to melt 35.0 g of ice at 0 °C is 11,690 J.