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:
Inferring is when a scientist uses reasoning to explain or interpret the things they observe
Answer:
D. Sweat evaporates from your skin
Explanation:
A physical change is a reversible process, no new substance is formed. A physical change does not affect the chemical composition of a substance.
Sweat evaporation from the skin is a physical change, because the change that occur is merely a change of state, Liquid to Gaseous state, no new substance is formed.
The mean kinetic energy per molecule is , where is the Boltzmann constant and T is the absolute temperature.
So at 1000°C, the T = 1273.15 K, kB=1.38 × 10-23, therefore the mean kinetic energy is 2.635 × 10⁻²⁰J.
<h3><u>
What is Kinetic energy ?</u></h3>
The energy an item has as a result of motion is known as kinetic energy.
A force must be applied to an item in order to accelerate it. We must put forth effort in order to apply a force. After the job is finished, energy is transferred to the item, which then moves at a new, constant speed. Kinetic energy is the type of energy that is transmitted and is dependent on the mass and speed attained.
Kinetic energy may be converted into other types of energy and transported between things. A flying squirrel may run into a chipmunk that is standing still, for instance. Some of the squirrel's original kinetic energy may have been transferred to the chipmunk or changed into another kind of energy after the impact.
To view more about kinetic energy, refer to;
brainly.com/question/2972267
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Physical changes occur when objects or substances undergo a change that does not change their chemical composition. This contrasts with the concept of chemical change in which the composition of a substance changes or one or more substances combine or break up to form new substances.
