Perbedaan Reaksi Eksoterm dan Endoterm

Summary

In this video, viewers learn about the difference between exothermic and endothermic reactions. The video first explains the concepts of system and environment, using the example of NaOH powder in HCl solution to illustrate these ideas. It then defines exothermic reactions, which release heat to the surroundings, as seen in the combustion of wood, and endothermic reactions, which absorb heat, like photosynthesis in plants. The video also includes energy level diagrams to further explain enthalpy changes in both types of reactions, making complex chemistry concepts easy to understand.

Takeaways

• 😀 A system is everything that is the center of focus, while the surroundings refer to everything outside the system.
• 😀 An example of a system is the NaOH powder and HCl solution in a test tube, while the surroundings include the test tube and the surrounding air.
• 😀 Exothermic reactions release heat into the surroundings, causing the surrounding temperature to rise.
• 😀 A common example of an exothermic reaction is the combustion of wood, which releases heat and warms the surrounding area.
• 😀 In an exothermic reaction, the enthalpy of the reactants is greater than the enthalpy of the products, resulting in a negative change in enthalpy (ΔH).
• 😀 The combustion of methanol is an example of an exothermic reaction, with a negative enthalpy change of -638 kJ.
• 😀 Endothermic reactions absorb heat from the surroundings, causing the temperature of the surroundings to drop.
• 😀 Photosynthesis is an example of an endothermic reaction where plants absorb energy from sunlight to produce food.
• 😀 In an endothermic reaction, the enthalpy of the reactants is smaller than the enthalpy of the products, resulting in a positive change in enthalpy (ΔH).
• 😀 The formation of acetylene gas is an example of an endothermic reaction, with a positive enthalpy change of +226.7 kJ.

Q & A

What is the definition of a system in the context of chemical reactions?

In the context of chemical reactions, a system is everything that is the focus of attention, such as the reactants or substances involved in the reaction.

What is considered the environment in a chemical reaction?

The environment refers to everything outside the system, including things like the container holding the reactants and the surrounding air.

What is an exothermic reaction?

An exothermic reaction is a type of chemical reaction that releases heat into the surroundings, resulting in an increase in the temperature of the environment.

Can you give an example of an exothermic reaction?

A common example of an exothermic reaction is the combustion of wood, where heat is released into the environment.

How does an exothermic reaction affect the surroundings?

In an exothermic reaction, heat flows from the system to the surroundings, making the surrounding temperature increase, which is why you might feel warmth near a burning object.

What does the energy diagram of an exothermic reaction look like?

In an exothermic reaction, the energy of the reactants is higher than the energy of the products, leading to a negative change in enthalpy (ΔH).

What is an endothermic reaction?

An endothermic reaction is a type of chemical reaction that absorbs heat from the surroundings, causing the surrounding temperature to decrease.

Can you give an example of an endothermic reaction?

An example of an endothermic reaction is photosynthesis, where plants absorb energy from sunlight to convert carbon dioxide and water into glucose.

How does an endothermic reaction affect the surroundings?

In an endothermic reaction, heat is absorbed from the surroundings, leading to a decrease in the temperature of the surrounding area.

What does the energy diagram of an endothermic reaction look like?

In an endothermic reaction, the energy of the reactants is lower than the energy of the products, resulting in a positive change in enthalpy (ΔH).