What amount of heat is required to completely melt a 29.95-gram sample of #H_2O#(s) at 0° C?

Question

Jeremiah Adams · Accepted Answer

#"9.990 kJ"#

The question wants you to determine how much heat will be required in order to get a #"29.95-g"# sample of ice to undergo a solid #-># liquid phase change at its melting point of #0^@"C"#.

So, in essence, all you need to know in order to answer this question is the value of water's enthalpy of fusion, #DeltaH_"fus"#.

In essence, the enthalpy of fusion provides information about one thing from two different angles.

In your case, water is going from solid to liquid, so #DeltaH_"fus"# will be positive. For water, you have

#DeltaH_"fus" = "333.55 J g"^(-1)#

Encyclopy of Fusion, https://tutor.hix.ai

So, if you need #"333.55 J"# in order to get #"1 g"# of ice at #0^@"C"# to go to liquid water at #0^@"C"#, it follows that #"29.95 g"# of ice would require

#29.95 color(red)(cancel(color(black)("g"))) * overbrace("333.55 J"/(1color(red)(cancel(color(black)("g")))))^(color(blue)(DeltaH_"fus")) = "9989.8 J"#

The response, rounded to four sig figs, is

#"heat required " = color(green)(" 9990. J")#

Kilojoules, when expressed, will have

#"heat required " = color(green)(" 9.990 kJ")#

Luna Chen · Answer

undefined 6.007 kJ