Answer:
ΔHrxn = -635.14kJ/mol
Explanation:
We can make algebraic operations of reactions until obtain the desire reaction and, ΔH of the reaction must be operated in the same way to obtain the ΔH of the desire reaction (Hess's law). Using the reactions:
(1)Ca(s) + 2 H+(aq) → Ca2+(aq) + H2(g) ΔH = 1925.9 kJ/mol
(2) 2H2(g) + O2 g) → 2 H2O(l) ΔH = −571.68 kJ/mole
(3) CaO(s) + 2 H+(aq) → Ca2+(aq) + H2O(l) ΔH = 2275.2 kJ/mole
Reaction (1) - (3) produce:
Ca(s) + H2O(l) → H2(g) + CaO(s)
ΔH = 1925.9kJ/mol - 2275.2kJ/mol = -349.3kJ/mol
Now this reaction + 1/2(2):
Ca(s) + ½ O2(g) → CaO(s)
ΔH = -349.3kJ/mol + 1/2 (-571.68kJ/mol)
<h3>ΔHrxn = -635.14kJ/mol</h3>
Answer:
<h2>
The bombing of Hiroshima ended World War II.</h2>
Explanation:
[The scientific method includes these steps:
Observation
Hypothesis
Experimentation
Data Analysis
Conclusion]
The first two Hypothesis can be tested with the scientific method, you cannot go back in time and observe or experiment with the bombing of Hiroshima to deduce whether or not it ended World War II.
Answer:
B. hydrogen
Explanation:
that's because hydrogen is an element.
Answer:
222.2 grams of CaCl2 in 2 moles
Explanation:
Mole=given mass/gram mass formula
2moles=x/Gram Mass Formula
(Gram Mass Formula of CaCl2):
Ca=40.1
Cl= 35.5 x 2= 71
-----------------------
GFM=111.1
2 moles = x/111.1 g
x=222.2
