When ice melts, the physicals state changes from solid to liquid. The energy or the heat required (q) required to change a unit mass (m) of a substance from solid to liquid is known as the enthalpy or heat of fusion (ΔHf). The variables; q, m and ΔHf are related as:
q = m * ΔHf
the mass of ice m = 65 g
the heat of fusion of water at 0C = ΔHf = 334 J/g
Therefore: q = 65 g * 334 J/g = 21710 J
Now:
4.184 J = 1 cal
which implies that: 21710 J = 1 cal * 21710 J/4.184 J = 5188.8 cal
Hence the heat required is 5188.8 cal or 5.2 Kcal (approx)
Answer:
there must be free-moving electrons in a compound to conduct electricity.
in solid ionic compounds, there are no free electrons so it can't conduct electricity.
But in aqueous form the forces of attraction are broken and the ions (cations and anions) are free to move. This means there are free electrons that allow the aqueous compound to conduct electricity.
This type of formula is use in chemistry it has Iron ,Sodium, Hydroxyl and Chloride unit s in the equation.
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potassium reacts the most vigorously.
