Isotope Chemistry Example 1

Follow the full solution, then compare it with the other examples linked below.

Example 1

easy
Carbon has three naturally occurring isotopes: 12C{}^{12}\text{C}, 13C{}^{13}\text{C}, and 14C{}^{14}\text{C}. How many protons and neutrons does each have?

Solution

  1. 1
    Isotopes of the same element have the same atomic number but different mass numbers. All carbon isotopes have Z=6Z = 6, so each has 6 protons.
  2. 2
    Use the formula N=A−ZN = A - Z to find neutrons for each isotope: 12C{}^{12}\text{C}: 12−6=612 - 6 = 6 neutrons; 13C{}^{13}\text{C}: 13−6=713 - 6 = 7 neutrons; 14C{}^{14}\text{C}: 14−6=814 - 6 = 8 neutrons.
  3. 3
    Summary: 12C{}^{12}\text{C} (6n), 13C{}^{13}\text{C} (7n), 14C{}^{14}\text{C} (8n) — same element, different neutron counts.

Answer

12C: 6p, 6n13C: 6p, 7n14C: 6p, 8n{}^{12}\text{C: 6p, 6n}\quad {}^{13}\text{C: 6p, 7n}\quad {}^{14}\text{C: 6p, 8n}
Isotopes are atoms of the same element (same number of protons) that differ in the number of neutrons. They have identical chemical properties but different masses.

About Isotope

Atoms of the same element that have the same number of protons but different numbers of neutrons, giving them different mass numbers.

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More Isotope Examples

Example 2 medium

Boron has two stable isotopes: [formula] (19.9%) and [formula] (80.1%). Calculate the average atomic

Example 3 hard

Copper has two stable isotopes: [formula] and [formula]. The average atomic mass of copper is [formu

Example 4 medium

Chlorine-35 and chlorine-37 are both chlorine. What is different about them, and what stays the same

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