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Alenkasestr [34]
3 years ago
6

Write the ΔH system for each of the following changes in physical state

Chemistry
1 answer:
8_murik_8 [283]3 years ago
4 0

Answer:

a. positive

b. negative

c. positive

d. negative

Explanation:

In a exothermic reaction, heat is written as a product (del H is negative), whereas in an endothermic reaction heat is written on the reaction side (del H is positive).

For a, it is endothermic process. We know this because to go from solid to liquid you need to put energy into the system. When we put energy into a chemical system it is said to be an endothermic reaction.

For b, it is exothermic reaction. This is because you have to lose the extra energy to go from less ordered states (gas) to more ordered state (liquid). Gas is less ordered because its molecules are freely moving and such. Another way of thinking about this question is just putting the heat on product side and think if I was going in reverse direction I would put heat in product because I would need to add heat to liquid to turn to gas (and if heat is added to product side we know its exothermic). Two ways of thinking whichever you prefer.

The rest have similar explaination.

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Select the reason why two molecules of benzaldehyde cannot react via the aldol condensation.
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3 years ago
According to Maslow's hierarchy of needs, the basic needs are what we call physiological or biological needs. The survival of th
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Answer:

<u>True</u>

Explanation:

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Answer: (3) molecules have different molecular structures.


Explanation:


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3) The bonds is what define the structure and properties of the substances, so since O₂ has only two bonds and O₃ has three bonds, the properties and behaviors of the element are different.


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3 years ago
Balancing equations<br> I'll give brainliest.
wel

Answer:

You should follow these steps:

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Place coefficients, as needed, in front of the symbols or formulas to increase the number of atoms or molecules of the substances.

Repeat steps 1 and 2 until the equation is balanced.

Explanation:

7 0
2 years ago
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