The city itself. Maybe from body heat and human activities.
Answer:
ΔHr = -275 kj
Explanation:
It is possible to obtain the net change in enthalpy for the formation of one mole of lead(II) sulfate from lead, lead(IV) oxide, and sulfuric acid using the reactions:
(1) H₂SO₄(l) → SO₃(g) + H₂O (l) ΔH=+113kJ
(2) Pb(s) + PbO₂(s) + 2SO₃(g) → 2PbSO₄(s) ΔH=−775kJ
If you sum (1) + ¹/₂(2) you will obtain:
H₂SO₄(l) + ¹/₂Pb(s) + ¹/₂PbO₂(s) → PbSO₄(s) + H₂O(l)
Using Hess's law, the net change in enthalpy for this reaction could be obtained as:
ΔHr = ΔH(1) + ¹/₂ΔH(2)
ΔHr = +113kJ + ¹/₂ -775kJ
ΔHr = -275 kJ
Answer:
Hi
The water molecule is composed of three atoms: an oxygen atom and two hydrogen atoms. Very strong electromagnetic forces hold the atoms inside the molecule.
A parallel electromagnetic attraction exists between the molecules individually. Water molecules are constantly moving and continuously form and break bonds with other molecules. As the temperature rises, the molecules move faster and the bonds weaken, changing their state to gas. This is called the boiling point. At this stage, the distance between water molecules is large and intermolecular bonds are almost non-existent.
Explanation:
A. is the answer, because the more an experiment is repeated, it will become apparent if it yields the same results thus confirming or debunking the hypothesis.