Calculate the energy change when 50.0 g of water evaporates (Hyap = 2250 kJ/g). Molar mass for water 18 g/mol

in simple steps

1 answer

To calculate the energy change when 50.0 g of water evaporates, we can use the formula:

Energy change = mass * heat of vaporization

First, let's convert the mass of water from grams to moles using the molar mass of water (18 g/mol):

50.0 g / 18 g/mol = 2.78 mol

Now, let's calculate the energy change using the heat of vaporization (Hyap) and the number of moles:

Energy change = 2.78 mol * 2250 kJ/g

To cancel out grams, we need to convert grams to kilograms:

50.0 g = 50.0 g * (1 kg / 1000 g) = 0.05 kg

Now, calculate the energy change:

Energy change = 2.78 mol * 2250 kJ/g * 0.05 kg
Energy change = 312.75 kJ