CHEMISTRY MIDDLE SCHOOL

8. What is the heat of reaction when hydrogen and oxygen combine to form water?2H2(g) + O2(g) → 2H2O(1)
(AHC H20(I) = -285.8 kJ/mol)
A -120.9 kJ
B-241.8 kJ
C-571.6 kJ
D-285.8 kJ

Answers

Answer 1
Answer:

Answer:

The heat of reaction when hydrogen and oxygen combine to form water is :

C. 571.6 kJ

Explanation:

Enthalpy Change = The enthalpy change for the formation of 1 mole of the substance from their standard state is called the enthalpy of formation.

This is intensive quantity as it is fixed for 1 mole .

Intensive properties = Those properties which are independent on the amount of the substance are intensive properties.

The value of these quantities does not get halve if you divide the substance into two equal parts. example , density, refractive index.

However , the enthalpy of reaction is extensive. Because on increasing the amount the value of the enthalpy also get doubles

Hence for this reaction :

2H_(2)(g)+O_(2)\rightarrow 2H_(2)(l)

Its value is -285.8 kJ for 1 mole

And here two moles are present . so the value of molar enthalpy is:

-285.8 x 2 = -571.6 kJ

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B) What happens to the soup water when elisya blows it harder with the soap bubble blower
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Answers

The soup water would turn into soap.

Final answer:

When Elisya blows harder with the bubble blower, she increases the air pressure and thus the bubble's size due to resistance against the surface tension of the water. Additionally, the soap bubble's film thickness changes, altering light path differences and possibly the perceived color of the bubble.

Explanation:

When Elisya blows harder on the soup with the bubble blower, the soup water may experience changes due to increased air pressure. This air adds stress to the surfaces of the water which can cause a bubble to form as the surface tension of the water attempts to decrease the surface area.

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Also, the formation of soap bubbles has to do with the properties of thin films and light interference which are evident when we see distinct colors on the soap bubbles. When Elisya blows harder through the soap bubble blower, the thickness of the bubble's film changes, altering the path length difference and interferences of light, which could potentially change the colors we perceive in the bubble.

Learn more about Surface Tension and Bubbles here:

brainly.com/question/31322269

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Answers

Each mineral has its own properties different from other minerals because minerals are made up of different elements. Different elements which can be found on the periodic table all have unique properties, therefore, gold will have distinct properties in comparison with zinc or aluminium for example because they are made up of different elements :))))
I hope this is helpful
have a nice day

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Answers

Answer:

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Explanation:

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Answers

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Answers

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Explanation:

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