Free Printable Protons Neutrons and Electrons Practice Worksheets - Free Printable
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Step-by-step solution for: Free Printable Protons Neutrons and Electrons Practice Worksheets
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Step-by-step solution for: Free Printable Protons Neutrons and Electrons Practice Worksheets
Here are the solutions to your worksheet problems. I have worked through each step carefully to ensure the answers are correct.
To fill this table, we use these rules:
* Protons: This is the Atomic Number (found on the periodic table). It defines the element.
* Electrons: In a neutral atom, this number is the same as the number of Protons.
* Atomic Mass: This is usually rounded to the nearest whole number found on the periodic table.
* Neutrons: Calculated by subtracting Protons from the Atomic Mass ($Mass - Protons = Neutrons$).
Row 1: Hydrogen (H)
* Protons: 1 (Given)
* Electrons: 1 (Same as protons)
* Atomic Mass: The periodic table lists Hydrogen as approx 1.008, so we round to 1.
* Neutrons: $1 (\text{Mass}) - 1 (\text{Proton}) =$ 0.
Row 2: Helium (He)
* Atomic Mass: 4 (Given)
* Looking at the periodic table, Helium is element #2.
* Protons: 2
* Electrons: 2
* Neutrons: $4 (\text{Mass}) - 2 (\text{Protons}) =$ 2.
Row 3: Carbon (C)
* Protons: 6 (Given). Element #6 is Carbon.
* Symbol: C
* Electrons: 6 (Same as protons)
* Atomic Mass: Periodic table lists Carbon as approx 12.01, so we round to 12.
* Neutrons: $12 (\text{Mass}) - 6 (\text{Protons}) =$ 6.
Row 4: Nitrogen (N)
* Neutrons: 7 (Given)
* Looking at the periodic table, Nitrogen is element #7.
* Protons: 7
* Electrons: 7
* Atomic Mass: $7 (\text{Protons}) + 7 (\text{Neutrons}) =$ 14.
Row 5: Oxygen (O)
* Looking at the periodic table, Oxygen is element #8.
* Protons: 8
* Electrons: 8
* Atomic Mass: Periodic table lists Oxygen as approx 16.00, so 16.
* Neutrons: $16 (\text{Mass}) - 8 (\text{Protons}) =$ 8.
Row 6: Sodium (Na)
* Looking at the periodic table, Sodium is element #11.
* Protons: 11
* Electrons: 11
* Atomic Mass: Periodic table lists Sodium as approx 22.99, so we round to 23.
* Neutrons: $23 (\text{Mass}) - 11 (\text{Protons}) =$ 12.
Row 7: Chlorine (Cl)
* Looking at the periodic table, Chlorine is element #17.
* Protons: 17
* Electrons: 17
* Atomic Mass: Periodic table lists Chlorine as approx 35.45. In these problems, we typically round to the nearest whole number, which is 35.
* Neutrons: $35 (\text{Mass}) - 17 (\text{Protons}) =$ 18.
Row 8: Iron (Fe)
* Looking at the periodic table, Iron is element #26.
* Protons: 26
* Electrons: 26
* Atomic Mass: Periodic table lists Iron as approx 55.85, so we round to 56.
* Neutrons: $56 (\text{Mass}) - 26 (\text{Protons}) =$ 30.
***
* Protons: Look up Uranium (U) on the periodic table. It is element number 92. So, it has 92 protons.
* Electrons: In a neutral atom, electrons equal protons. So, it has 92 electrons.
* Neutrons: The number "235" is the mass number. To find neutrons, subtract protons from the mass: $235 - 92 = 143$. So, it has 143 neutrons.
***
* Element: The identity of an element is determined by the number of protons. Look for element number 18 on the periodic table. Element 18 is Argon (Ar).
* Atomic Mass: Add the protons and neutrons together. $18 + 22 = 40$. The atomic mass is 40 amu.
***
* Protons: Look up Sodium (Na) on the periodic table. It is element number 11. So, 11 protons.
* Electrons: Equal to the number of protons. So, 11 electrons.
* Neutrons: Subtract the protons from the mass number (23). $23 - 11 = 12$. So, 12 neutrons.
***
* Protons: Look up Aluminum (Al) on the periodic table. It is element number 13. So, 13 protons.
* Electrons: Equal to the number of protons. So, 13 electrons.
* Neutrons: Subtract the protons from the mass number (27). $27 - 13 = 14$. So, 14 neutrons.
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Final Answer:
1. Table Completion:
| Element | Symbol | Protons | Neutrons | Electrons | Atomic Mass (amu) |
| :--- | :---: | :---: | :---: | :---: | :---: |
| Hydrogen | H | 1 | 0 | 1 | 1 |
| Helium | He | 2 | 2 | 2 | 4 |
| Carbon | C | 6 | 6 | 6 | 12 |
| Nitrogen | N | 7 | 7 | 7 | 14 |
| Oxygen | O | 8 | 8 | 8 | 16 |
| Sodium | Na | 11 | 12 | 11 | 23 |
| Chlorine | Cl | 17 | 18 | 17 | 35 |
| Iron | Fe | 26 | 30 | 26 | 56 |
2. Uranium-235:
* Protons: 92
* Neutrons: 143
* Electrons: 92
3. Unknown Atom:
* Atomic Mass: 40 amu
* Element: Argon (Ar)
4. Sodium-23:
* Protons: 11
* Neutrons: 12
* Electrons: 11
5. Aluminum-27:
* Protons: 13
* Neutrons: 14
* Electrons: 13
1. Using the periodic table, fill in the blanks.
To fill this table, we use these rules:
* Protons: This is the Atomic Number (found on the periodic table). It defines the element.
* Electrons: In a neutral atom, this number is the same as the number of Protons.
* Atomic Mass: This is usually rounded to the nearest whole number found on the periodic table.
* Neutrons: Calculated by subtracting Protons from the Atomic Mass ($Mass - Protons = Neutrons$).
Row 1: Hydrogen (H)
* Protons: 1 (Given)
* Electrons: 1 (Same as protons)
* Atomic Mass: The periodic table lists Hydrogen as approx 1.008, so we round to 1.
* Neutrons: $1 (\text{Mass}) - 1 (\text{Proton}) =$ 0.
Row 2: Helium (He)
* Atomic Mass: 4 (Given)
* Looking at the periodic table, Helium is element #2.
* Protons: 2
* Electrons: 2
* Neutrons: $4 (\text{Mass}) - 2 (\text{Protons}) =$ 2.
Row 3: Carbon (C)
* Protons: 6 (Given). Element #6 is Carbon.
* Symbol: C
* Electrons: 6 (Same as protons)
* Atomic Mass: Periodic table lists Carbon as approx 12.01, so we round to 12.
* Neutrons: $12 (\text{Mass}) - 6 (\text{Protons}) =$ 6.
Row 4: Nitrogen (N)
* Neutrons: 7 (Given)
* Looking at the periodic table, Nitrogen is element #7.
* Protons: 7
* Electrons: 7
* Atomic Mass: $7 (\text{Protons}) + 7 (\text{Neutrons}) =$ 14.
Row 5: Oxygen (O)
* Looking at the periodic table, Oxygen is element #8.
* Protons: 8
* Electrons: 8
* Atomic Mass: Periodic table lists Oxygen as approx 16.00, so 16.
* Neutrons: $16 (\text{Mass}) - 8 (\text{Protons}) =$ 8.
Row 6: Sodium (Na)
* Looking at the periodic table, Sodium is element #11.
* Protons: 11
* Electrons: 11
* Atomic Mass: Periodic table lists Sodium as approx 22.99, so we round to 23.
* Neutrons: $23 (\text{Mass}) - 11 (\text{Protons}) =$ 12.
Row 7: Chlorine (Cl)
* Looking at the periodic table, Chlorine is element #17.
* Protons: 17
* Electrons: 17
* Atomic Mass: Periodic table lists Chlorine as approx 35.45. In these problems, we typically round to the nearest whole number, which is 35.
* Neutrons: $35 (\text{Mass}) - 17 (\text{Protons}) =$ 18.
Row 8: Iron (Fe)
* Looking at the periodic table, Iron is element #26.
* Protons: 26
* Electrons: 26
* Atomic Mass: Periodic table lists Iron as approx 55.85, so we round to 56.
* Neutrons: $56 (\text{Mass}) - 26 (\text{Protons}) =$ 30.
***
2. Uranium-235 (U-235) atom consists of how many protons, neutrons, and electrons?
* Protons: Look up Uranium (U) on the periodic table. It is element number 92. So, it has 92 protons.
* Electrons: In a neutral atom, electrons equal protons. So, it has 92 electrons.
* Neutrons: The number "235" is the mass number. To find neutrons, subtract protons from the mass: $235 - 92 = 143$. So, it has 143 neutrons.
***
3. Determine the atomic mass of an atom with 18 protons, 22 neutrons, and 18 electrons. What element is it?
* Element: The identity of an element is determined by the number of protons. Look for element number 18 on the periodic table. Element 18 is Argon (Ar).
* Atomic Mass: Add the protons and neutrons together. $18 + 22 = 40$. The atomic mass is 40 amu.
***
4. A Sodium-23 (Na-23) atom has how many protons, neutrons, and electrons?
* Protons: Look up Sodium (Na) on the periodic table. It is element number 11. So, 11 protons.
* Electrons: Equal to the number of protons. So, 11 electrons.
* Neutrons: Subtract the protons from the mass number (23). $23 - 11 = 12$. So, 12 neutrons.
***
5. Calculate the number of protons, neutrons, and electrons in an atom of Aluminum-27 (Al-27).
* Protons: Look up Aluminum (Al) on the periodic table. It is element number 13. So, 13 protons.
* Electrons: Equal to the number of protons. So, 13 electrons.
* Neutrons: Subtract the protons from the mass number (27). $27 - 13 = 14$. So, 14 neutrons.
──────────────────────────────────────
Final Answer:
1. Table Completion:
| Element | Symbol | Protons | Neutrons | Electrons | Atomic Mass (amu) |
| :--- | :---: | :---: | :---: | :---: | :---: |
| Hydrogen | H | 1 | 0 | 1 | 1 |
| Helium | He | 2 | 2 | 2 | 4 |
| Carbon | C | 6 | 6 | 6 | 12 |
| Nitrogen | N | 7 | 7 | 7 | 14 |
| Oxygen | O | 8 | 8 | 8 | 16 |
| Sodium | Na | 11 | 12 | 11 | 23 |
| Chlorine | Cl | 17 | 18 | 17 | 35 |
| Iron | Fe | 26 | 30 | 26 | 56 |
2. Uranium-235:
* Protons: 92
* Neutrons: 143
* Electrons: 92
3. Unknown Atom:
* Atomic Mass: 40 amu
* Element: Argon (Ar)
4. Sodium-23:
* Protons: 11
* Neutrons: 12
* Electrons: 11
5. Aluminum-27:
* Protons: 13
* Neutrons: 14
* Electrons: 13
Parent Tip: Review the logic above to help your child master the concept of proton electron neutron worksheet.
