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san4es73 [151]
2 years ago
13

Instant hot and cold packs are found in many common stores and work when two substances react. Depending on the substances that

react, the reaction either absorbs heat or gives off heat.
The enthalpy of a hot pack is
A. negative
B. positive
C. zero
because the reaction
A. absorbs heat
B. gives off heat
C. does not change temperature
Chemistry
2 answers:
OLga [1]2 years ago
7 0

Answer:

b positive and b gives off heat

Flura [38]2 years ago
3 0

Answer: negative and gives off heat

Explanation:

On edge

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