Answer:
Step-by-step explanation:
a substance's enthalpy of fusion tells you how much heat is needed in order to convert
1 g
of said substance from solid at its melting point to liquid at its melting point.
In water's case, an enthalpy of fusion equal to
333.55 J g
−
1
tells you that
1 g
of ice at
0
∘
C
can be converted to
1 g
of liquid water at
0
∘
C
by supplying
333.55 J
of heat.
Your ice cube has a mass of
55.0 g
, which means that it will require
55.0
g
⋅
=
Δ
H
fus
333.55 J
1
g
=
18,345.25 J
Rounded to three sig figs, the number of sig figs you have for the mass of the ice cube, the answer will be
heat needed
=
∣
∣
∣
∣
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
a
a
18,300 J
a
a
∣
∣
−−−−−−−−−−