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

1. o2(g)as a product

Read the sentences below in 1962, i tried to enroll as the first black student at the university of mississippi. the governor of mississippi blocked my entrance which best describes the verbs used in the sentences? o they are past tense verbs, which are often used in narrative essays o they are past tense verbs, which are not often used in narrative essays. o they are future tense verbs, which are often used in narrative essays o they are future tense verbs, which are not often used in narrative essays.

Your question is not clear but if you can explain yourself i would be glad to .  just trying to : ))