During a chemistry class, the teacher explained that chlorine does not exist as a single type of atom in nature. Instead, it occurs as two naturally occurring isotopes:
- Chlorine-35 \((^{35}Cl)\) with an abundance of \(75\)%
- Chlorine-37 \((^{37}Cl)\) with an abundance of \(25\)%
The teacher asked the students to calculate the average atomic mass of chlorine. Some students concluded that since chlorine has isotopes of masses \(35\) u and \(37\) u, its atomic mass should simply be \(36\) u. However, another student argued that the abundance of each isotope must also be considered.
Based on the given information, answer the following questions.
1. Why is the average atomic mass of chlorine not equal to 36 u?
2. If chlorine contained equal numbers of
\(^{35}Cl\) and
\(^{37}Cl\) atoms, what would its average atomic mass be?