This video is about what exothermic and endothermic reactions are and how temperature changes can be used to identify which reaction is which. Exothermic reactions, in solution, give out energy ...

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There are four hypersensitivity classifications: types 1, 2, 3, and 4. Types 1, 2, and 3 are immediate hypersensitivity reactions that occur soon after an allergen exposure. Type 4 is classified as ...