Answer:
ΔH = -20kJ
Explanation:
The enthalpy of formation of a compound is defined as the change of enthalpy during the formation of 1 mole of the substance from its constituent elements. For H₂S(g) the reaction that describes this process is:
H₂(g) + S(g) → H₂S(g)
Using Hess's law, it is possible to sum the enthalpies of several reactions to obtain the change in enthalpy of a particular reaction thus:
<em>(1) </em>H₂S(g) + ³/₂O₂(g) → SO₂(g) + H₂O(g) ΔH = -519 kJ
<em>(2) </em>H₂(g) + ¹/₂O₂(g) → H₂O(g) ΔH = -242 kJ
<em>(3) </em>S(g) + O₂(g) → SO₂(g) ΔH = -297 kJ
The sum of -(1) + (2) + (3) gives:
<em>-(1) </em>SO₂(g) + H₂O(g) → H₂S(g) + ³/₂O₂(g) ΔH = +519 kJ
<em>(2) </em>H₂(g) + ¹/₂O₂(g) → H₂O(g) ΔH = -242 kJ
<em>(3) </em>S(g) + O₂(g) → SO₂(g) ΔH = -297 kJ
<em>-(1) + (2) + (3): </em><em>H₂(g) + S(g) → H₂S(g) </em>
<em>ΔH =</em> +519kJ - 242kJ - 297kJ = <em>-20 kJ</em>
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I hope it helps!
Number of O atoms : 24
<h3>Further explanation</h3>
Given
C₆H₁₂O₆ compound
Required
Number of atoms
Solution
A molecular formula shows the number of atomic elements in compound.
The empirical formula is the smallest comparison of the atoms
Glucose-C₆H₁₂O₆ is composed of 3 elements, namely C, H, and O.
The number of atoms in a compound can usually be seen from the subscript number after the atom and the reaction coefficient shows the number of molecules
So number of O atoms :
= 4 x 6 = 24 atoms
Answer:
g NaCl = 424.623 g
Explanation:
<em>C</em> NaCl = 3.140 m = 3.140 mol NaCl / Kg solvent
∴ solvent: H2O
∴ mass H2O = 2.314 Kg
mol NaCl:
⇒ mol NaCl = (3.140 mol NaCl/Kg H2O)×(2.314 Kg H2O) = 7.266 mol NaCl
∴ mm NaCl = 58.44 g/mol
⇒ g NaCl = (7.266 mol NaCl)×(58.44 g/mol) = 424.623 g NaCl
Answer:
heat can move from any source but if we are being legitimate it moves from convection
Explanation: