Answer:
ΔH°rxn = -827.5 kJ
Explanation:
Let's consider the following balanced equation.
2 PbS(s) + 3 O₂(g) → 2 PbO(s) + 2 SO₂(g)
We can calculate the standard enthalpy of reaction (ΔH°rxn) from the standard enthalpies of formation (ΔH°f) using the following expression.
ΔH°rxn = [2 mol × ΔH°f(PbO(s)) + 2 mol × ΔH°f(SO₂(g)
)] - [2 mol × ΔH°f(PbS(s)) + 3 mol × ΔH°f(O₂(g)
)]
ΔH°rxn = [2 mol × ΔH°f(PbO(s)) + 2 mol × ΔH°f(SO₂(g)
)] - [2 mol × ΔH°f(PbS(s)) + 3 mol × ΔH°f(O₂(g)
)]
ΔH°rxn = [2 mol × (-217.32 kJ/mol) + 2 mol × (-296.83)] - [2 mol × (-100.4) + 3 mol × 0 kJ/mol]
ΔH°rxn = -827.5 kJ
The base of toothpaste is magnesium hydroxide.
Answer:
Population of duck and frog will change with the change
Explanation:
The complete question is
Scientists are studying animals in a large lake area. In this lake area, both owls and raccoons eat ducks, and ducks eat frogs. The data shows that recently the size of the raccoon population decreased. How will the decrease in the raccoon population affect the other populations? Be sure to explain whether the owl population, the duck population, and the frog population will change, and why.
- Owl population will change
-
Duck population will change
-
Frog population will change
Solution
Raccoon eat duck and duck eat frog. Now if the population of Raccoon decreases then the number of predators of duck will decrease thereby increasing the population of duck.
The higher will be the number of ducks, the more frogs they will consume thereby decreasing the population of frogs
Hence both the population of duck and frog will change with the change
Answer:
315.51g/mol
Explanation:
137(33 + (16.00 + 1.01) 2 + 8 [1.01 (2) + 16.00] = 315.51g/mol
In Virginia, the continental divide separates the New River from the Roanoake and James River. East of the continental divide, the rivers flow east or south toward the Atlantic Ocean. West of the continental divide, the rivers flow north or west toward the Gulf of Mexico by way of the Ohio and the Mississippi Rivers.