When you use a chemical cold pack, you squeeze the room temperature contents together until the mixture becomes very cold. A friend comments that chemical reaction must be “giving off coldness”, so that your hands are "freezing cold". Comment on the validity of this statement given your understanding of thermodynamics.

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.

girl imma just put my comment here because i need a couple point okurrttt

one negative thing it that it can kill water animals. another negative thing is it can cause the destruction of ecosystem. one way water pollution can be reduced is to conserve energy.