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!
Answer:
c. contraction
Explanation:
Heating will cause substances to expand, or change their state (like solid to liquid) or it may be a chemical reaction.
Answer:
Atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. A chemical bond is a force of attraction between atoms or ions
Explanation:
Answer: $46.98
Explanation:
The distance to drive to Los Angeles from San Francisco is 405 miles. Since the car get 25 miles per gallon of gas, for 405 miles, the car will use:
= 405/25 = 16.2 gallons
Since the cost of gasoline is $2.90 a gallon and the car will use 16.2 gallons. The cost will be:
= $2.90 × 16.2 gallons
= $46.98
hydrogen and oxygen atoms
Explanation:
this is because they are non metals and there will be sharing of electrons between the two atoms forming the bond
