When we describe different isotopes of the same element, such as Carbon-12, Carbon-13, and Carbon-14, what is the main difference between them?

Question

BlackTom AI · Accepted Answer

They have different numbers of neutrons.

1) Relevant knowledge points and concepts
- An element is defined by its atomic number (number of protons). All carbon atoms have 6 protons.
- Isotopes are atoms of the same element that differ in mass due to different numbers of neutrons in the nucleus.
- Mass number (A) = protons (Z) + neutrons (N). Neutral atoms have electrons equal to protons.

2) Step-by-step reasoning
- For carbon isotopes labeled Carbon-12, Carbon-13, Carbon-14, the number after the element is the mass number A.
- Since carbon’s atomic number Z = 6 (protons = 6) for all three, the neutron count N = A − Z.
- Compute neutrons for each isotope to see the difference.

3) Calculations (intermediate steps shown)
- Carbon-12: N = 12 − 6 = 6 neutrons.
- Carbon-13: N = 13 − 6 = 7 neutrons.
- Carbon-14: N = 14 − 6 = 8 neutrons.
Thus the isotopes differ by having 6, 7, and 8 neutrons respectively.

4) Why the correct answer is correct
- Because the proton number (6) is identical for all carbon isotopes, the only nuclear variable that changes among Carbon-12, -13, and -14 is the neutron count. That difference in neutrons changes the mass and nuclear stability (e.g., C-14 is radioactive), but not the element’s identity.

5) Why other possible alternatives are incorrect
- Different numbers of protons: would produce a different element (e.g., 7 protons = nitrogen), so this is not an isotope of carbon.
- Different numbers of electrons: would create ions, not isotopes; neutral isotopes of carbon have the same number of electrons (6).
- Different chemical identity: isotopes of the same element have nearly identical chemical behavior because electron configurations are the same; only subtle mass-related effects (kinetic isotope effects) occur.

6) Conclusion
The main difference among Carbon-12, Carbon-13, and Carbon-14 is their number of neutrons, which matches the provided correct answer: They have different numbers of neutrons.

When we describe different isotopes of the same element, such as Carbon-12, Carbon-13, and Carbon-14, what is the main difference between them?单项选择题

类似问题

An atom of Beryllium isotope has in its nucleus

Which of the following best describes an Isotope?

How many protons, neutrons and electrons are in selenium − 77?

Why do different isotopes of the same element have similar chemistry?

Which pair represents a set of isotopes?

The atomic mass of rhenium is 186.2 amu. It has two naturally occurring isotopes. Given that 37.1% of natural rhenium is rhenium–185, what is the other stable isotope?

Isotopes of an element differ in that they have the same number of [ Select ] neutrons protons but different numbers of [ Select ] neutrons protons .

Isotopes of an element differ in that they have the same number of protons but different numbers of neutrons .

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单