The Alka Seltzer tablet contains Citric acid which causes it to react in pure water. Why is Acetic acid also added to the reaction?

Both models are effective because they show the valence electrons, and these valence electrons indicate the reactivity of an element.

Replicate prove reliability and validity

Standing in the sunlight and feeling the heat on your face (uv radiation is entering the skin, converting to infrared radiation, and is absorbed by your tissues)orstanding near a fire and feeling the heat on your skin (infrared radiation transfer)

Answerδh > 0explanationc₆h₆  (s)  → c₆h₆ (l)if you are changing it from a solid to a liquid, you are pretty much melting the solid. this requires heat energy. therefore, the reaction is endothermic (takes in energy); the system enthalpy increases as the reaction proceeds: δh > 0.