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:
Only one—(i), or (ii), or (iii)—increases the reaction rate.
Explanation:
<em>Which of the following changes always leads to an increase in the rate constant for a reaction?</em>
- <em>Decreasing the temperature. </em>NO. A lower temperature leads to a slower reaction because the molecules have less energy to react.
- <em>Decreasing the activation energy</em>. YES. According to the Arrhenius equation, the lower the activation energy, the higher the rate constant.
- <em>Making the value of ΔE more negative</em>. NO. A more negative ΔE means a reaction is more spontaneous but not faster.
Nanochemicals can be defined as chemicals generated by using nanomaterials (materials that possess of size on nanometer dimensions). The nanochemicals are used in multiple different applications including chemical warfare, bicycle making, armor design and military weapons crafting. The most commonly used and observed nanochemicals are carbon nanotubes that are used a ton in industry for applications such as stronger materials (stronger bicycles).
Smart materials are exquisitely designed materials whose property(ies) can be modified with the use of an external stimulus such as temperature, stress, pH, and so on. Some examples of smart materials include shape memory materials, piezoelectric materials, ferrofluids, self-healing materials, and such. Applications involve memory pillows, memory based solar panels (for satellites), light sensitive glasses, and so on.
Specialized materials are made specifically to perform a specified task or function. Applications involve electronic equipment (high purity silicon & germanium), machine tools (high tungsten high carbon steel), dental filling (dental amalgam), and so on.
Answer:
It cannot conduct electricity, however adding salt or sugar will make the water have impurities/other substance making it easier to conduct electricity
Explanation:
Distilled water by itself does not contain impurities, thus, it cannot <em>conduct </em>electricity.
When you put salt in water, the water molecules pull the sodium and chlorine ions apart so they are floating freely, increasing the conductivity.
For more information, please refer to the internet :D
Have fun studying, and goodluck!
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Answer:
The difference between them is that renewable energy is something that can be used practically and not run out. Non-renewable energy has a limited supply.
Explanation:
Renewable energy is better for the environment as it is not something that takes millions of years to form, as some non-renewable energy sources are.
Brainliest please! :>
