Periodic Table Facts worksheet for identifying element symbols, atomic numbers, and element groups.

Let's solve this step-by-step based on the worksheet titled "Periodic Table Facts".

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Part 1: Identify the symbol for each element

We need to write the chemical symbol for each element listed.

| Number | Element | Symbol |
|--------|---------------|--------|
| 1 | Oxygen | O |
| 2 | Hydrogen | H |
| 3 | Chlorine | Cl |
| 4 | Sodium | Na |
| 5 | Fluorine | F |
| 6 | Carbon | C |
| 7 | Helium | He |
| 8 | Nitrogen | N |
| 9 | Copper | Cu |
| 10 | Sulfur | S |
| 11 | Magnesium | Mg |
| 12 | Manganese | Mn |
| 13 | Neon | Ne |
| 14 | Bromine | Br |
| 15 | Phosphorus | P |
| 16 | Silver | Ag |
| 17 | Lead | Pb |
| 18 | Iron | Fe |
| 19 | Calcium | Ca |
| 20 | Potassium | K |

> ✔ Note: "Phosphorous" is a common misspelling; the correct spelling is Phosphorus, symbol P.

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Part 2: Fill in the chart

We are given a table with some data and need to complete it.

| Element | Symbol | Atomic Number | Period | Group |
|-----------|--------|----------------|--------|-------|
| Sodium | Na | 11 | 3 | 1 |
| O | O | 8 | 2 | 16 |
| Krypton | Kr | 36 | 4 | 18 |
| | Au | 79 | 6 | 11 |
| | Mn | 25 | 4 | 7 |

#### Let’s go row by row:

1. O (Oxygen):
- Symbol: O
- Atomic number: 8
- Period: 2 (2nd row)
- Group: 16 (Chalcogens)

2. Krypton (Kr):
- Symbol: Kr
- Atomic number: 36
- Period: 4
- Group: 18 (Noble gases)

3. Atomic number 79 → Gold (Au):
- Symbol: Au
- Atomic number: 79
- Period: 6
- Group: 11

4. Period 4, Group 7 → Manganese (Mn):
- Symbol: Mn
- Atomic number: 25
- Period: 4
- Group: 7

✔ So the completed table looks like:

| Element | Symbol | Atomic Number | Period | Group |
|-----------|--------|----------------|--------|-------|
| Sodium | Na | 11 | 3 | 1 |
| Oxygen | O | 8 | 2 | 16 |
| Krypton | Kr | 36 | 4 | 18 |
| Gold | Au | 79 | 6 | 11 |
| Manganese | Mn | 25 | 4 | 7 |

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Part 3: Give an atom with the following characteristics

We need to provide one example of an element that fits each category.

| Letter | Category | Example | Reasoning |
|--------|------------------------|----------------|----------|
| a | Halogen | Cl (Chlorine) | Group 17 elements (F, Cl, Br, I, At) |
| b | Chalcogen | S (Sulfur) | Group 16 elements (O, S, Se, Te, Po) |
| c | Alkali metal | Na (Sodium) | Group 1 metals (Li, Na, K, etc.) |
| d | Actinide series | U (Uranium) | Elements from Ac (89) to Lr (103) |
| e | Lanthanide series | Ce (Cerium) | Elements from La (57) to Lu (71) |
| f | Alkaline Earth metal | Mg (Magnesium) | Group 2 metals (Be, Mg, Ca, etc.) |
| g | Transition metal | Fe (Iron) | Elements in Groups 3–12 (e.g., Fe, Ni, Cu) |
| h | Nobel gas | Ne (Neon) | Group 18 (He, Ne, Ar, Kr, Xe, Rn) |

> ✔ Note: “Nobel gas” is a typo — should be Noble gas.

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✔ Final Answers:

#### Part 1: Symbols
1. O
2. H
3. Cl
4. Na
5. F
6. C
7. He
8. N
9. Cu
10. S
11. Mg
12. Mn
13. Ne
14. Br
15. P
16. Ag
17. Pb
18. Fe
19. Ca
20. K

#### Part 2: Chart
| Element | Symbol | Atomic Number | Period | Group |
|-----------|--------|----------------|--------|-------|
| Sodium | Na | 11 | 3 | 1 |
| Oxygen | O | 8 | 2 | 16 |
| Krypton | Kr | 36 | 4 | 18 |
| Gold | Au | 79 | 6 | 11 |
| Manganese | Mn | 25 | 4 | 7 |

#### Part 3: Characteristics
a. Halogen → Cl
b. Chalcogen → S
c. Alkali metal → Na
d. Actinide series → U
e. Lanthanide series → Ce
f. Alkaline Earth metal → Mg
g. Transition metal → Fe
h. Noble gas → Ne

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