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Atomic Structure Fundamentals
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Atomic Structure Fundamentals
📚 Part 1: Multiple Choice
1. What is the atomic number of an element?
The number of electrons in the atom
The number of protons in the nucleus
The number of neutrons in the nucleus
The total mass of the atom
2. Which particles are found in the nucleus of an atom?
Protons
Neutrons
Electrons
Quarks
3. Carbon-12 and Carbon-14 are examples of:
Different elements
Isotopes
Ions
Compounds
4. If an atom has 6 protons and 8 neutrons, what is its mass number?
6
8
14
2
✏️ Part 2: Atomic Calculations
5. Complete the table below for the given atoms:
| Element | Atomic Number | Mass Number | Protons | Neutrons | Electrons |
|---|---|---|---|---|---|
| Oxygen-16 | 8 | 16 | ____ | ____ | ____ |
| Sodium-23 | ____ | 23 | 11 | ____ | ____ |
| Chlorine-35 | 17 | ____ | ____ | 18 | ____ |
6. An atom has 20 protons and 22 neutrons. Calculate:
a) Atomic number: __________
b) Mass number: __________
c) Number of electrons in a neutral atom: __________
d) Name of the element: __________
7. Explain the difference between atomic number and mass number:
🎨 Part 3: Atomic Models and Applications
8. Draw and label a simple atomic model for Lithium-7 (atomic number 3) in the box below. Include the nucleus, protons, neutrons, and electrons in their energy levels.
9. Carbon-14 is used in archaeological dating. If Carbon-14 has 6 protons, how many neutrons does it have? Show your working:
10. Explain why isotopes of the same element have similar chemical properties but different physical properties:
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