CARA MENENTUKAN JUMLAH PROTON, ELEKTRON, NEUTRON | KIMIA SMA KELAS X

Summary

In this educational chemistry video, the presenter teaches how to calculate the number of protons, electrons, and neutrons of an element, using potassium as an example. Viewers learn that the mass number of potassium is 39, the atomic number is 19, and that the number of protons equals the atomic number. To calculate neutrons, the presenter subtracts the atomic number from the mass number, revealing 20 neutrons. The number of electrons is also equal to the number of protons for a neutral atom. This step-by-step explanation simplifies the concept of atomic structure for learners.

Takeaways

• 😀 The lesson is focused on teaching how to calculate the number of protons, electrons, and neutrons in an element.
• 😀 The example used in the video is potassium, which has a mass number of 39 and an atomic number of 19.
• 😀 The mass number is the sum of protons and neutrons, and in the case of potassium, it is 39.
• 😀 The atomic number represents the number of protons in an element. For potassium, this is 19.
• 😀 The number of protons is always equal to the atomic number. Therefore, potassium has 19 protons.
• 😀 To calculate the number of neutrons, subtract the atomic number from the mass number. For potassium, 39 (mass number) - 19 (atomic number) = 20 neutrons.
• 😀 The number of electrons in a neutral atom is the same as the number of protons, which is 19 for potassium.
• 😀 The video emphasizes the relationship between atomic number, protons, neutrons, and electrons in an element.
• 😀 The script highlights that no electrons are gained or lost in the example, meaning the number of electrons equals the number of protons.
• 😀 The video encourages viewers to ask questions or seek clarification through the comments section for further understanding.

Q & A

What is the purpose of the lesson in the script?

The purpose of the lesson is to teach students how to calculate the number of protons, neutrons, and electrons for an element, using potassium (K) as an example.

What is the significance of the number 39 in the potassium example?

The number 39 represents the mass number of potassium, which is the sum of the protons and neutrons in the atom.

What does the atomic number represent in the potassium example?

The atomic number, which is 19 for potassium, represents the number of protons in the atom and, in a neutral atom, the number of electrons as well.

How do you calculate the number of neutrons in an atom?

To calculate the number of neutrons, subtract the atomic number from the mass number. For potassium, this is 39 (mass number) - 19 (atomic number) = 20 neutrons.

What does the number 19 represent in the potassium example?

The number 19 represents both the atomic number of potassium and the number of protons and electrons in a neutral atom.

Why are the number of protons and electrons the same in a neutral atom?

In a neutral atom, the number of protons equals the number of electrons to balance out the charges, ensuring the atom has no overall charge.

What is the formula to calculate the number of neutrons?

The formula to calculate the number of neutrons is: Neutrons = Mass number - Atomic number.

What is the role of the teacher in this lesson?

The teacher explains the concepts step by step, using potassium as an example, and helps students understand how to calculate protons, neutrons, and electrons.

Is the method described in the lesson applicable to all elements?

Yes, the method for calculating protons, neutrons, and electrons using the atomic number and mass number applies to all elements.

What is the overall structure of the lesson?

The lesson starts with an introduction, then explains the concepts with an example of potassium, and concludes by encouraging students to ask questions for further clarification.