Solved 2 S 44.95 Scan 35 Y 88.905 Yttriu 57-7 Lanthanic | Chegg.com - Free Printable
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Step-by-step solution for: Solved 2 S 44.95 Scan 35 Y 88.905 Yttriu 57-7 Lanthanic | Chegg.com
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Show Answer Key & Explanations
Step-by-step solution for: Solved 2 S 44.95 Scan 35 Y 88.905 Yttriu 57-7 Lanthanic | Chegg.com
Let's go through the Protons, Neutrons, and Electrons Practice Worksheet step by step to ensure all entries are correct and explain how to solve each part.
---
- Atomic Number (Z) = number of protons
- Mass Number (A) = protons + neutrons → so:
- Neutrons = Mass Number – Atomic Number
- Electrons = protons in a neutral atom
- Valence Electrons = electrons in the outermost shell (use periodic table group for main-group elements)
- Electron Energy Levels = Period number (row on the periodic table)
---
Now, let’s check each row one by one and correct or verify your answers.
---
- Mass Number: 11
- Atomic Number: 5
- Protons: 5 ✔
- Neutrons: 11 – 5 = 6 ✔
- Electrons: 5 ✔
- Valence Electrons: Group 13 → 3 ✔
- Electron Energy Levels: Period 2 → 2 ✘ *(You left blank)*
✔ Corrected: 2
---
- Mass Number: 24
- Atomic Number: 11
- Protons: 11 ✔
- Neutrons: 24 – 11 = 13 ✔
- Electrons: 11 ✔
- Valence Electrons: Group 1 → 1 ✘ *(You wrote 2)*
✘ Correction: 1
- Electron Energy Levels: Period 3 → 3 ✘ *(You left blank)*
✔ Corrected: 3
---
- Mass Number: 89
- Atomic Number: 39
- Protons: 39 ✔
- Neutrons: 89 – 39 = 50 ✔
- Electrons: 39 ✔
- Valence Electrons: Transition metal → 3 (commonly loses 3 electrons) ✔
- Electron Energy Levels: Period 5 → 5 ✘ *(You left blank)*
✔ Corrected: 5
---
- Mass Number: 63
- Atomic Number: 29
- Protons: 29 ✔
- Neutrons: 63 – 29 = 34 ✔
- Electrons: 29 ✔
- Valence Electrons: Transition metal → usually 1 or 2, but often 1 (Cu⁺) ✔
- Electron Energy Levels: Period 4 → 4 ✘ *(You left blank)*
✔ Corrected: 4
---
- Mass Number: 98
- Atomic Number: 43? ✘
- Wait! Tellurium has atomic number 52, not 43.
- You wrote atomic number as 43 → that’s Technetium (Tc).
⚠️ Mistake: Element is Tellurium (Te), not Tc.
Let’s fix this:
- Tellurium (Te):
- Symbol: Te ✔
- Mass Number: 98 ✔
- Atomic Number: 52 ✘ *(you wrote 43)*
- Protons: 52 ✘ *(you wrote 43)*
- Neutrons: 98 – 52 = 46 ✘ *(you wrote 55)*
- Electrons: 52 ✘ *(you wrote 43)*
- Valence Electrons: Group 16 → 6 ✘ *(you wrote 7)*
- Electron Energy Levels: Period 5 → 5 ✘ *(you wrote 7)*
✔ Corrected:
- Atomic Number: 52
- Protons: 52
- Neutrons: 46
- Electrons: 52
- Valence Electrons: 6
- Energy Levels: 5
> ⚠️ This row is incorrect — you accidentally used Technetium instead of Tellurium.
---
- Mass Number: 207
- Atomic Number: 82
- Protons: 82 ✔
- Neutrons: 207 – 82 = 125 ✔
- Electrons: 82 ✔
- Valence Electrons: Group 14 → 4 ✔
- Electron Energy Levels: Period 6 → 6 ✘ *(you wrote 4)*
✔ Corrected: 6
---
- Mass Number: 204
- Atomic Number: 81
- Protons: 81 ✔
- Neutrons: 204 – 81 = 123 ✘ *(you wrote 26)*
- 26 is way too low. 204 – 81 = 123
- Electrons: 81 ✔
- Valence Electrons: Group 13 → 3 ✔
- Electron Energy Levels: Period 6 → 6 ✘ *(you wrote 3)*
✔ Corrected:
- Neutrons: 123
- Energy Levels: 6
---
- Mass Number: 1
- Atomic Number: 1
- Protons: 1 ✔
- Neutrons: 1 – 1 = 0 ✔
- Electrons: 1 ✔
- Valence Electrons: Group 1 → 1 ✘ *(you wrote 4)*
- Electron Energy Levels: Period 1 → 1 ✘ *(you wrote 4)*
✔ Corrected:
- Valence Electrons: 1
- Energy Levels: 1
---
- Mass Number: 12
- Atomic Number: 6
- Protons: 6 ✔
- Neutrons: 12 – 6 = 6 ✔
- Electrons: 6 ✔
- Valence Electrons: Group 14 → 4 ✔
- Electron Energy Levels: Period 2 → 2 ✘ *(you left blank)*
✔ Corrected: 2
---
- Mass Number: 14
- Atomic Number: 7
- Protons: 7 ✔
- Neutrons: 14 – 7 = 7 ✔
- Electrons: 7 ✔
- Valence Electrons: Group 15 → 5 ✔
- Electron Energy Levels: Period 2 → 2 ✘ *(you left blank)*
✔ Corrected: 2
---
- Mass Number: 137
- Atomic Number: 56
- Protons: 56 ✔
- Neutrons: 137 – 56 = 81 ✔
- Electrons: 56 ✔
- Valence Electrons: Group 2 → 2 ✔
- Electron Energy Levels: Period 6 → 6 ✘ *(you wrote 2)*
✔ Corrected: 6
---
- Mass Number: 40
- Atomic Number: 20
- Protons: 20 ✔
- Neutrons: 40 – 20 = 20 ✔
- Electrons: 20 ✔
- Valence Electrons: Group 2 → 2 ✔
- Electron Energy Levels: Period 4 → 4 ✘ *(you wrote 2)*
✔ Corrected: 4
---
- Mass Number: 28
- Atomic Number: 14
- Protons: 14 ✔
- Neutrons: 28 – 14 = 14 ✔
- Electrons: 14 ✔
- Valence Electrons: Group 14 → 4 ✔
- Electron Energy Levels: Period 3 → 3 ✘ *(you wrote 4)*
✔ Corrected: 3
---
- Mass Number: 40
- Atomic Number: 18
- Protons: 18 ✔
- Neutrons: 40 – 18 = 22 ✔
- Electrons: 18 ✔
- Valence Electrons: Group 18 → 8 ✔
- Electron Energy Levels: Period 3 → 3 ✘ *(you wrote 2)*
✔ Corrected: 3
---
- Mass Number: 24
- Atomic Number: 12
- Protons: 12 ✔
- Neutrons: 24 – 12 = 12 ✔
- Electrons: 12 ✔
- Valence Electrons: Group 2 → 2 ✔
- Electron Energy Levels: Period 3 → 3 ✘ *(you wrote 2)*
✔ Corrected: 3
---
## 📝 Summary of Corrections:
| Element | Mistake | Correction |
|--------|--------|-----------|
| Sodium (Na) | Valence e⁻ = 2 | → 1 |
| | Energy levels = ? | → 3 |
| Yttrium (Y) | Energy levels = ? | → 5 |
| Copper (Cu) | Energy levels = ? | → 4 |
| Tellurium (Te) | Wrong element (used Tc) | → Use Te, Z=52, N=46, valence=6, levels=5 |
| Lead (Pb) | Energy levels = 4 | → 6 |
| Thallium (Tl) | Neutrons = 26 | → 123, levels = 6 |
| Hydrogen (H) | Valence = 4, levels = 4 | → 1, 1 |
| Carbon (C) | Energy levels = ? | → 2 |
| Nitrogen (N) | Energy levels = ? | → 2 |
| Barium (Ba) | Energy levels = 2 | → 6 |
| Calcium (Ca) | Energy levels = 2 | → 4 |
| Silicon (Si) | Energy levels = 4 | → 3 |
| Argon (Ar) | Energy levels = 2 | → 3 |
| Magnesium (Mg) | Energy levels = 2 | → 3 |
---
## ✔ Final Answer Summary (Corrected):
| Element | Protons | Neutrons | Electrons | Valence e⁻ | Energy Levels |
|--------|--------|---------|----------|------------|---------------|
| Boron | 5 | 6 | 5 | 3 | 2 |
| Sodium | 11 | 13 | 11 | 1 | 3 |
| Yttrium | 39 | 50 | 39 | 3 | 5 |
| Copper | 29 | 34 | 29 | 1 | 4 |
| Tellurium | 52 | 46 | 52 | 6 | 5 |
| Lead | 82 | 125 | 82 | 4 | 6 |
| Thallium | 81 | 123 | 81 | 3 | 6 |
| Hydrogen | 1 | 0 | 1 | 1 | 1 |
| Carbon | 6 | 6 | 6 | 4 | 2 |
| Nitrogen | 7 | 7 | 7 | 5 | 2 |
| Barium | 56 | 81 | 56 | 2 | 6 |
| Calcium | 20 | 20 | 20 | 2 | 4 |
| Silicon | 14 | 14 | 14 | 4 | 3 |
| Argon | 18 | 22 | 18 | 8 | 3 |
| Magnesium | 12 | 12 | 12 | 2 | 3 |
---
- Always double-check element symbols and atomic numbers using the periodic table.
- Remember: Period = energy level, Group = valence electrons (for main-group elements).
- For transition metals, valence electrons vary — use common oxidation states or research.
Let me know if you'd like a printable version or help with another worksheet! 😊
---
🔍 Key Concepts Recap:
- Atomic Number (Z) = number of protons
- Mass Number (A) = protons + neutrons → so:
- Neutrons = Mass Number – Atomic Number
- Electrons = protons in a neutral atom
- Valence Electrons = electrons in the outermost shell (use periodic table group for main-group elements)
- Electron Energy Levels = Period number (row on the periodic table)
---
Now, let’s check each row one by one and correct or verify your answers.
---
✔ 1. Boron (B)
- Mass Number: 11
- Atomic Number: 5
- Protons: 5 ✔
- Neutrons: 11 – 5 = 6 ✔
- Electrons: 5 ✔
- Valence Electrons: Group 13 → 3 ✔
- Electron Energy Levels: Period 2 → 2 ✘ *(You left blank)*
✔ Corrected: 2
---
✔ 2. Sodium (Na)
- Mass Number: 24
- Atomic Number: 11
- Protons: 11 ✔
- Neutrons: 24 – 11 = 13 ✔
- Electrons: 11 ✔
- Valence Electrons: Group 1 → 1 ✘ *(You wrote 2)*
✘ Correction: 1
- Electron Energy Levels: Period 3 → 3 ✘ *(You left blank)*
✔ Corrected: 3
---
✔ 3. Yttrium (Y)
- Mass Number: 89
- Atomic Number: 39
- Protons: 39 ✔
- Neutrons: 89 – 39 = 50 ✔
- Electrons: 39 ✔
- Valence Electrons: Transition metal → 3 (commonly loses 3 electrons) ✔
- Electron Energy Levels: Period 5 → 5 ✘ *(You left blank)*
✔ Corrected: 5
---
✔ 4. Copper (Cu)
- Mass Number: 63
- Atomic Number: 29
- Protons: 29 ✔
- Neutrons: 63 – 29 = 34 ✔
- Electrons: 29 ✔
- Valence Electrons: Transition metal → usually 1 or 2, but often 1 (Cu⁺) ✔
- Electron Energy Levels: Period 4 → 4 ✘ *(You left blank)*
✔ Corrected: 4
---
✔ 5. Tellurium (Te)
- Mass Number: 98
- Atomic Number: 43? ✘
- Wait! Tellurium has atomic number 52, not 43.
- You wrote atomic number as 43 → that’s Technetium (Tc).
⚠️ Mistake: Element is Tellurium (Te), not Tc.
Let’s fix this:
- Tellurium (Te):
- Symbol: Te ✔
- Mass Number: 98 ✔
- Atomic Number: 52 ✘ *(you wrote 43)*
- Protons: 52 ✘ *(you wrote 43)*
- Neutrons: 98 – 52 = 46 ✘ *(you wrote 55)*
- Electrons: 52 ✘ *(you wrote 43)*
- Valence Electrons: Group 16 → 6 ✘ *(you wrote 7)*
- Electron Energy Levels: Period 5 → 5 ✘ *(you wrote 7)*
✔ Corrected:
- Atomic Number: 52
- Protons: 52
- Neutrons: 46
- Electrons: 52
- Valence Electrons: 6
- Energy Levels: 5
> ⚠️ This row is incorrect — you accidentally used Technetium instead of Tellurium.
---
✔ 6. Lead (Pb)
- Mass Number: 207
- Atomic Number: 82
- Protons: 82 ✔
- Neutrons: 207 – 82 = 125 ✔
- Electrons: 82 ✔
- Valence Electrons: Group 14 → 4 ✔
- Electron Energy Levels: Period 6 → 6 ✘ *(you wrote 4)*
✔ Corrected: 6
---
✔ 7. Thallium (Tl)
- Mass Number: 204
- Atomic Number: 81
- Protons: 81 ✔
- Neutrons: 204 – 81 = 123 ✘ *(you wrote 26)*
- 26 is way too low. 204 – 81 = 123
- Electrons: 81 ✔
- Valence Electrons: Group 13 → 3 ✔
- Electron Energy Levels: Period 6 → 6 ✘ *(you wrote 3)*
✔ Corrected:
- Neutrons: 123
- Energy Levels: 6
---
✔ 8. Hydrogen (H)
- Mass Number: 1
- Atomic Number: 1
- Protons: 1 ✔
- Neutrons: 1 – 1 = 0 ✔
- Electrons: 1 ✔
- Valence Electrons: Group 1 → 1 ✘ *(you wrote 4)*
- Electron Energy Levels: Period 1 → 1 ✘ *(you wrote 4)*
✔ Corrected:
- Valence Electrons: 1
- Energy Levels: 1
---
✔ 9. Carbon (C)
- Mass Number: 12
- Atomic Number: 6
- Protons: 6 ✔
- Neutrons: 12 – 6 = 6 ✔
- Electrons: 6 ✔
- Valence Electrons: Group 14 → 4 ✔
- Electron Energy Levels: Period 2 → 2 ✘ *(you left blank)*
✔ Corrected: 2
---
✔ 10. Nitrogen (N)
- Mass Number: 14
- Atomic Number: 7
- Protons: 7 ✔
- Neutrons: 14 – 7 = 7 ✔
- Electrons: 7 ✔
- Valence Electrons: Group 15 → 5 ✔
- Electron Energy Levels: Period 2 → 2 ✘ *(you left blank)*
✔ Corrected: 2
---
✔ 11. Barium (Ba)
- Mass Number: 137
- Atomic Number: 56
- Protons: 56 ✔
- Neutrons: 137 – 56 = 81 ✔
- Electrons: 56 ✔
- Valence Electrons: Group 2 → 2 ✔
- Electron Energy Levels: Period 6 → 6 ✘ *(you wrote 2)*
✔ Corrected: 6
---
✔ 12. Calcium (Ca)
- Mass Number: 40
- Atomic Number: 20
- Protons: 20 ✔
- Neutrons: 40 – 20 = 20 ✔
- Electrons: 20 ✔
- Valence Electrons: Group 2 → 2 ✔
- Electron Energy Levels: Period 4 → 4 ✘ *(you wrote 2)*
✔ Corrected: 4
---
✔ 13. Silicon (Si)
- Mass Number: 28
- Atomic Number: 14
- Protons: 14 ✔
- Neutrons: 28 – 14 = 14 ✔
- Electrons: 14 ✔
- Valence Electrons: Group 14 → 4 ✔
- Electron Energy Levels: Period 3 → 3 ✘ *(you wrote 4)*
✔ Corrected: 3
---
✔ 14. Argon (Ar)
- Mass Number: 40
- Atomic Number: 18
- Protons: 18 ✔
- Neutrons: 40 – 18 = 22 ✔
- Electrons: 18 ✔
- Valence Electrons: Group 18 → 8 ✔
- Electron Energy Levels: Period 3 → 3 ✘ *(you wrote 2)*
✔ Corrected: 3
---
✔ 15. Magnesium (Mg)
- Mass Number: 24
- Atomic Number: 12
- Protons: 12 ✔
- Neutrons: 24 – 12 = 12 ✔
- Electrons: 12 ✔
- Valence Electrons: Group 2 → 2 ✔
- Electron Energy Levels: Period 3 → 3 ✘ *(you wrote 2)*
✔ Corrected: 3
---
## 📝 Summary of Corrections:
| Element | Mistake | Correction |
|--------|--------|-----------|
| Sodium (Na) | Valence e⁻ = 2 | → 1 |
| | Energy levels = ? | → 3 |
| Yttrium (Y) | Energy levels = ? | → 5 |
| Copper (Cu) | Energy levels = ? | → 4 |
| Tellurium (Te) | Wrong element (used Tc) | → Use Te, Z=52, N=46, valence=6, levels=5 |
| Lead (Pb) | Energy levels = 4 | → 6 |
| Thallium (Tl) | Neutrons = 26 | → 123, levels = 6 |
| Hydrogen (H) | Valence = 4, levels = 4 | → 1, 1 |
| Carbon (C) | Energy levels = ? | → 2 |
| Nitrogen (N) | Energy levels = ? | → 2 |
| Barium (Ba) | Energy levels = 2 | → 6 |
| Calcium (Ca) | Energy levels = 2 | → 4 |
| Silicon (Si) | Energy levels = 4 | → 3 |
| Argon (Ar) | Energy levels = 2 | → 3 |
| Magnesium (Mg) | Energy levels = 2 | → 3 |
---
## ✔ Final Answer Summary (Corrected):
| Element | Protons | Neutrons | Electrons | Valence e⁻ | Energy Levels |
|--------|--------|---------|----------|------------|---------------|
| Boron | 5 | 6 | 5 | 3 | 2 |
| Sodium | 11 | 13 | 11 | 1 | 3 |
| Yttrium | 39 | 50 | 39 | 3 | 5 |
| Copper | 29 | 34 | 29 | 1 | 4 |
| Tellurium | 52 | 46 | 52 | 6 | 5 |
| Lead | 82 | 125 | 82 | 4 | 6 |
| Thallium | 81 | 123 | 81 | 3 | 6 |
| Hydrogen | 1 | 0 | 1 | 1 | 1 |
| Carbon | 6 | 6 | 6 | 4 | 2 |
| Nitrogen | 7 | 7 | 7 | 5 | 2 |
| Barium | 56 | 81 | 56 | 2 | 6 |
| Calcium | 20 | 20 | 20 | 2 | 4 |
| Silicon | 14 | 14 | 14 | 4 | 3 |
| Argon | 18 | 22 | 18 | 8 | 3 |
| Magnesium | 12 | 12 | 12 | 2 | 3 |
---
🧠 Tips for Future:
- Always double-check element symbols and atomic numbers using the periodic table.
- Remember: Period = energy level, Group = valence electrons (for main-group elements).
- For transition metals, valence electrons vary — use common oxidation states or research.
Let me know if you'd like a printable version or help with another worksheet! 😊
Parent Tip: Review the logic above to help your child master the concept of periodic table protons neutrons and electrons worksheet.
