Compare the amount of heat required to vaporize a 200.-gram sample of H20(L) at its boiling point to the amount of heat required to melt a 200.-gram sample ofH20(s) at its melting point.

how much kj of heat are required to vaporize 42.8 grams of c3 h10 o (deltaH vap=26.5 kj/mol)

To compare the amount of heat required to vaporize a 200-gram sample of H2O (liquid) at its boiling point to the amount of heat required to melt a 200-gram sample of H2O (solid) at its melting point, we need to calculate the heat involved in each process separately.

Let's break it down step by step:

1. Find the heat required to vaporize the 200-gram sample of H2O (liquid) at its boiling point:

The heat required to vaporize a substance is given by the formula:

Q = m * ΔHv

Where:
Q is the heat required (in Joules)
m is the mass of the substance (in grams)
ΔHv is the heat of vaporization (in J/g)

The heat of vaporization of water is typically around 40.7 kJ/mol or 40.7 J/g.

So, for our 200-gram sample of H2O(L) at its boiling point, we can calculate the heat required using the following equation:

Q1 = 200 g * 40.7 J/g = 8,140 J

The heat required to vaporize the 200-gram sample of H2O(L) at its boiling point is 8,140 Joules.

2. Find the heat required to melt the 200-gram sample of H2O (solid) at its melting point:

The heat required to melt a substance is given by the formula:

Q = m * ΔHf

Where:
Q is the heat required (in Joules)
m is the mass of the substance (in grams)
ΔHf is the heat of fusion (in J/g)

The heat of fusion of water is typically around 6.01 kJ/mol or 6.01 J/g.

Using the same equation as before, but substituting ΔHf, we can calculate the heat required to melt the 200-gram sample of H2O(s) at its melting point:

Q2 = 200 g * 6.01 J/g = 1,202 J

The heat required to melt the 200-gram sample of H2O(s) at its melting point is 1,202 Joules.

Comparing Q1 (8,140 J) with Q2 (1,202 J), we can see that it takes significantly more heat to vaporize the sample of H2O(L) compared to melting the sample of H2O(s).

vaporize water:

q = mass x heat vaporization

melt ice
q = mass ice x heat fusion

thanks