How many molecules (or formula units) are in 138.56 g C4H10 Express your answer using four significant figures.
1 answer:
You might be interested in
Answer:
= 25.05°C
Explanation:
Given:
the value of ΔHcomb (heat of combustion) for dimethylphthalate (C10H10O4) is = 4685 kJ/mol.
mass = 0.905g of dimethylphthalate
molar mass = 194.18g dimethylphthalate
number of moles of dimethylphthalate = ???
= 21.5°C
= 6.15 kJ/°C
= ???
since we have our molar mass and mass of dimethylphthalate ;we can determine the number of moles as;
0.905g of dimethylphthalate ×
number of moles of dimethylphthalate = 0.000466 moles
Heat released = moles of dimethylphthalate × heat of combustion
= 0.000466 moles × 4685 kJ
= 21.84 kJ
∴ Heat absorbed by the calorimeter =
21.84 kJ =6.15 kJ/°C
21.84 KJ =
21.84 KJ = - 132.225 kJ
21.84 KJ + 132.225 kJ =
154.065 kJ =
=
=25.05°C