As you go down a group on the periodic table, atomic radii tend to increase because elements with larger atomic numbers have more occupied electron levels which take up more space surrounding the nucleus.
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Answer:
10.8amu
Explanation:
Given parameters:
Abundance of B - 10 = 20% = 0.2
Abundance of B - 11 = 80% = 0.8
Unknown:
Atomic mass of Boron = ?
Solution:
The atomic mass of Boron can be can be calculated using the expression below;
Atomic mass = (abundance of B - 10 x mass of isotope B - 10 ) +( abundance of B - 11 x mass of isotope B- 11)
Atomic mass = (0.2 x 10) + (0.8 x 11) = 2 + 8.8 = 10.8amu
The answer would be D, all the above