Fill in the missing information on this atomic number worksheet, including atomic numbers, protons, and electrons for various elements.

Atomic Number Worksheet with a table for filling in element names, atomic numbers, number of protons, and number of electrons, followed by two questions about atomic number and electron-proton equality.

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Show Answer Key & Explanations Step-by-step solution for: Atomic Number, Mass Number, and Isotopes - Worksheet | Distance

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🔍 Key Concepts:

- Atomic number = number of protons in the nucleus.
- In a neutral atom, number of electrons = number of protons.
- The element can be identified using the atomic number (from the periodic table).
- For example:
- Atomic number 6 → Carbon
- Atomic number 9 → Fluorine
- Atomic number 19 → Potassium
- Atomic number 53 → Iodine

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✔ Filled-in Table:

| Element | Atomic Number | Number of Protons | Number of Electrons |
|---------------|----------------|--------------------|----------------------|
| Hydrogen | 1 | 1 | 1 |
| Carbon | 6 | 6 | 6 |
| Fluorine | 9 | 9 | 9 |
| Potassium | 19 | 19 | 19 |
| Bismuth | 83 | 83 | 83 |
| Oxygen | 8 | 8 | 8 |
| Manganese | 25 | 25 | 25 |
| Helium | 2 | 2 | 2 |
| Phosphorus | 15 | 15 | 15 |
| Neon | 10 | 10 | 10 |
| Iodine | 53 | 53 | 53 |

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🔎 Step-by-step Reasoning:

1. Hydrogen:
- Known element → Atomic number = 1
- Protons = 1, Electrons = 1 (neutral)

2. Atomic Number = 6 → Carbon
- Protons = 6, Electrons = 6

3. Protons = 9 → Atomic number = 9 → Fluorine
- Electrons = 9

4. Electrons = 19 → Neutral atom → Protons = 19 → Atomic number = 19 → Potassium

5. Bismuth:
- Symbol: Bi → Atomic number = 83
- So protons = 83, electrons = 83

6. Oxygen:
- Atomic number = 8
- Protons = 8, Electrons = 8

7. Atomic Number = 25 → Manganese
- Protons = 25, Electrons = 25

8. Protons = 2 → Atomic number = 2 → Helium
- Electrons = 2

9. Phosphorus:
- Atomic number = 15
- Protons = 15, Electrons = 15

10. Atomic Number = 10 → Neon
- Protons = 10, Electrons = 10

11. Protons = 53 → Atomic number = 53 → Iodine
- Electrons = 53

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✔ Answers to Questions:

#### 1) What is the atomic number?

> The atomic number is the number of protons in the nucleus of an atom. It determines the identity of the element and its position on the periodic table.

#### 2) Why is the number of electrons and protons in a neutral atom the same?

> In a neutral atom, the number of electrons equals the number of protons because protons have a positive charge (+1) and electrons have a negative charge (-1). For the atom to have no net charge (neutral), the positive and negative charges must balance out. Therefore, the number of protons must equal the number of electrons.

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