To solve the problem of identifying the symbols for the chemical elements that meet the criteria of having atomic numbers greater than 3 and atomic masses less than 11.2 atomic mass units (u), we need to consult information about these elements.
Here are the atomic numbers, symbols, and atomic masses for some relevant elements from the periodic table:
1. Hydrogen (H): Atomic Number = 1, Atomic Mass = 1.008 u
2. Helium (He): Atomic Number = 2, Atomic Mass = 4.0026 u
3. Lithium (Li): Atomic Number = 3, Atomic Mass = 6.94 u
4. Beryllium (Be): Atomic Number = 4, Atomic Mass = 9.0122 u
5. Boron (B): Atomic Number = 5, Atomic Mass = 10.81 u
6. Carbon (C): Atomic Number = 6, Atomic Mass = 12.01 u
7. Nitrogen (N): Atomic Number = 7, Atomic Mass = 14.01 u
8. Oxygen (O): Atomic Number = 8, Atomic Mass = 16.00 u
9. Fluorine (F): Atomic Number = 9, Atomic Mass = 19.00 u
10. Neon (Ne): Atomic Number = 10, Atomic Mass = 20.18 u
Now, let's filter these elements based on the given criteria:
- The atomic number must be greater than 3.
- The atomic mass must be less than 11.2 u.
We will check each element one by one:
1. Beryllium (Be):
- Atomic Number: 4 (greater than 3)
- Atomic Mass: 9.0122 (less than 11.2)
- Satisfies both criteria.
2. Boron (B):
- Atomic Number: 5 (greater than 3)
- Atomic Mass: 10.81 (less than 11.2)
- Satisfies both criteria.
3. Carbon (C):
- Atomic Number: 6 (greater than 3)
- Atomic Mass: 12.01 (greater than 11.2)
- Does not satisfy the atomic mass criteria.
4. Nitrogen (N), Oxygen (O), Fluorine (F), Neon (Ne):
- All have atomic numbers greater than 3 but atomic masses greater than 11.2 u.
- Do not satisfy the atomic mass criteria.
Thus, the symbols for the elements that meet the criteria of having atomic numbers greater than 3 and atomic masses less than 11.2 u are:
Be (Beryllium) and B (Boron)
