Question

Question #f2d08

Answer 1

There are many types of chemical reactions. However, this question seems to be getting at the basic chemical reactions,

1. Addition: a molecule or compound is synthesized
2. Decomposition: a molecule or compound decomposes
3. Neutralization: and acid and base "neutralize" each other
4. Metathesis: ions or ionic compounds are "traded around"
5. Reduction-oxidation: electrons are "traded around"
6. Combustion: generally, a hydrocarbon molecule is combusted with oxygen gas to produce water and carbon dioxide

Note: Clearly there is a lot more to know about each of these reactions (e.g. if the products are insoluble, if its energetically favorable, et cetera).

`"1"` is metathesis (2x), `"2"` is combustion (exothermic), `"3"` is reduction-oxidation metathesis (x1), `"4"` is metathesis (2x), `"5"` neutralization, `"6"` is an addition/reduction-oxidation, `"7"` is a decomposition, `"8"` is combustion (exothermic)

Determining if a reaction is endothermic or exothermic is a function of its enthalpy of reaction. Combustion reactions are generally exothermic. We'd use thermodynamic data (commonly available in your text) otherwise to distinguish each reaction further.