Question
Chemistry Question on Isotopes
The number of neutrons present in the more abundant isotope of boron is 'x'. Amorphous boron upon heating with air forms a product, in which the oxidation state of boron is 'y'. The value of x + y is ...
A
4
B
6
C
3
D
9
Answer
9
Explanation
Solution
The more abundant isotope of boron is 11B, which contains 6 neutrons (x = 6). When boron reacts with oxygen:
B + O2 → B2O3
In B2O3, boron has an oxidation state of +3 (y = 3). Thus, x + y = 6 + 3 = 9.