Boron exists as two stable isotopes; B-10 (19%) and B-11 (81%). Find out the average atomic weight of boron in the periodic table.
Correct answer: D. 10.8
- A. 11.2
- B. 10.2
- C. 10
- D. 10.8
Explanation
Considering that B-11 is more abundant (approx 80%), we can predict the average atomic weight to be nearer to 11 than 10 but still between these two numbers, thus 10.8.
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Mole calculations connect mass, number of particles and Avogadro's number, while balanced equations provide the mole ratios used in stoichiometry. Questions cover limiting and excess reactants, theoretical yield and percentage yield, including identifying which reactant is consumed first and comparing the actual product with the maximum possible product.
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