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professor190 [17]
2 years ago
7

Help me please !! is it A,B,C, or D ???

Chemistry
1 answer:
Nata [24]2 years ago
5 0
Ok, after doing an immense amount of research I came up with the most logical answer.

A. Is indicated by a negative enthrall sign.

Reasoning: an endothermic reaction is ice melting and the energy being more than its surroundings. Not specified to ice but as an example, ice is endothermic. That puts d and b out of the running leaving you left with a and c.

When I searched up enthalpy, it said “When a substance changes at constant pressure, enthalpy tells how much heat and work was added or removed from the substance.” Which is similar to c, right? Yeah, meaning both a and c are similar in that aspect.

The reason I decided to go with a is because heat is NOT released into the surrounding, exothermic reactions release energy and heat into the surrounding.
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Answer:

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Explanation:

The data they give us is:

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To find the empirical formula without knowing the grams of the compound, we find it per mole:

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