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The web resource gives a graphical description of the different types of reactions explored to this point. Think about the compound sodium bicarbonate. Which of the five different types of reactions is your compound involved in? Include information about heats of reaction and comment on whether the reaction is endothermic or exothermic and how the magnitude of this energy change compares with other reactions. Post an example of a reaction and describe what type it is and why.

Paper For Above instruction

Sodium bicarbonate, commonly known as baking soda, is a versatile compound that engages in various chemical reactions, primarily categorized as acid-base reactions, decomposition reactions, and sometimes neutralization processes. To accurately classify the reaction involving sodium bicarbonate, it is essential to examine its typical reactions, the associated heats of reaction, and the energy exchange involved in these processes.

One of the most well-known reactions involving sodium bicarbonate is its decomposition upon heating:

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2 NaHCO₃ (s) → Na₂CO₃ (s) + CO₂ (g) + H₂O (g)

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This is a decomposition reaction where sodium bicarbonate breaks down into sodium carbonate, carbon dioxide, and water vapor. It is commonly observed during baking when heated, resulting in leavening bread or cake. The heat of reaction (enthalpy change, ΔH) for this decomposition is approximately +146 kJ/mol (on the molar basis of NaHCO₃), indicating it is an endothermic process. In endothermic reactions, energy is absorbed from the surroundings, causing a cooling effect during the reaction, which aligns with the energy requirements for breaking chemical bonds in sodium bicarbonate.

In comparison to other reactions, the decomposition of sodium bicarbonate involves a moderate energy change. For example, the neutralization of hydrochloric acid with sodium hydroxide releases approximately -57 kJ/mol, exemplifying an exothermic reaction. The decomposition process is endothermic and requires significant heat input, especially in industrial or laboratory settings, which makes it distinct from many other typical reactions that may either release or absorb less energy.

Another reaction to consider is the acid-base reaction between sodium bicarbonate and hydrochloric acid:

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NaHCO₃ (s) + HCl (aq) → NaCl (aq) + H₂O (l) + CO₂ (g)

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This reaction is classified as a neutralization because it involves an acid reacting with a base. It is highly exothermic, with an enthalpy change around -70 kJ/mol. This release of energy manifests as heat, and the vigorous production of carbon dioxide gas characterizes the reaction's physical behavior. The energy released is comparatively smaller than heat absorbed during decomposition but still significant enough to cause swift bubbling and effervescence.

The amount of heat involved (positive or negative) in these reactions plays a crucial role in their applications and environmental impacts. For example, baking relies on endothermic decomposition, which requires careful temperature control to achieve dough leavening, whereas industrial neutralization reactions often exploit exothermic heat release for energy efficiency.

In summary, sodium bicarbonate participates predominantly in decomposition and acid-base reactions. The decomposition process is endothermic and involves a considerable energy input, whereas the acid-base neutralization is exothermic, releasing energy rapidly. Understanding the heats of these reactions provides insight into their practical applications and environmental effects. Recognizing whether a reaction is endothermic or exothermic, and the magnitude of energy exchange, is fundamental in controlling and optimizing processes in both industrial and everyday contexts.

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