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)
Sometimes negative sometimes positive, your answer is B!
ACIDIC BEHAVIOR OF SOLUTION
hooc are carboxyl groups
your r or amino groups are those unique structures which have different atoms in them. your nh2 groups are your hydrogen atoms
The chemical formula : 3HgBr₂(Mercury(II) bromide)
<h3>Further explanation</h3>
Given
The chemical formulas of Mercury and Bromine
Required
The appropriate chemical formula
Solution
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
The number of molecules is determined by the coefficient in front of the compound
the number of atoms is determined by the subscript after the atom and the coefficient
Three molecules⇒ coefficient = 3
one atom of Mercury ⇒Hg
two atoms of Bromine ⇒ Br₂
The chemical formula : 3HgBr₂
