Answer:
-767,2kJ
Explanation:
It is possible to sum enthalpies of half-reactions to obtain the enthalpy of a global reaction using Hess's law. For the reactions:
1) H₂(g) + ¹/₂O₂(g) ⟶ H₂O(g) ΔH₁= −241.8 kJ
2) X(s) + 2Cl₂(g) ⟶ XCl₄(s) ΔH₂= +361.7 kJ
3) ¹/₂H₂(g) + ¹/₂Cl₂(g) ⟶ HCl (g) ΔH₃= −92.3 kJ
4) X(s) + O₂(g) ⟶ XO₂(s) ΔH₄= − 607.9 kJ
5) H₂O(g) ⟶ H₂O(l) ΔH₅= − 44.0 kJ
The sum of (4) - (2) produce:
6) XCl₄(s) + O₂(g) ⟶ XO₂(s) + 2Cl₂(g) ΔH₆ = ΔH₄ - ΔH₂ = -969,6 kJ
(6) + 4×(3):
7) XCl₄(s) + 2H₂(g) + O₂(g) ⟶ XO₂(s) + 4HCl(g) ΔH₇ = ΔH₆ + 4ΔH₃= -1338,8 kJ
(7) - 2×(1):
8) XCl₄(s) + 2H₂O(g) ⟶ XO₂(s) + 4HCl(g) ΔH₈ = ΔH₇ - 2ΔH₁= -855,2kJ
(8) - 2×(5):
9) XCl₄(s) + 2H₂O(l) ⟶ XO₂(s) + 4HCl(g) ΔH₉ = ΔH₈ - 2ΔH₅= <em>-767,2kJ</em>
I hope it helps!
Answer:
The answer to your question is 16 g
Explanation:
Data
Percent by mass = 8%
Mass of the solution = 200 g
Mass of solute = ?
Formula
Percent by mass = mass of solute / mass of solution x 100
- Solve for mass of solute
Mass of solute = Percent by mass x mass of solution / 100
- Substitution
Mass of solute = 8 x 200 / 100
- Simplification
Mass of solute = 1600 / 100
- Result
Mass of solute = 16 g
A covalent bond is formed between H and Br
The structure of HBr is as follows
H —Br
Formal charge for atoms are the charges for individual atoms in compounds.
Formal charge can be calculated as follows ;
Formal charge of atom = number of valence electrons -( number of bonds + number of lone pair electrons)
H has 1 valence electron, 1 bond and 0 number of lone pair electrons
Formal charge of H = 1 -1 -0 = 0
H has 0 charge
Sodium metal forms at the cathode