Isotopes are atoms of the same element with the same number of protons but different numbers of neutrons.
Carbon Isotope Builder
Change the neutron count to create different isotopes.
Neutrons6
Mass Number (A)
12
Stability
Stable
C126
Chemical Properties
IDENTICAL.
Chemical reactions involve electrons. Since isotopes have the same electron configuration, they react in exactly the same way.
Physical Properties
DIFFERENT.
Physical properties (e.g., density, boiling point, rate of diffusion) depend on mass. Since isotopes have different masses (A), these properties vary.
Example: Hydrogen Isotopes
H
Protium
0 neutrons
99.98%
D
Deuterium
1 neutron
Heavy Water
T
Tritium
2 neutrons
Radioactive
Student Practice Set
1.
Why do isotopes have the same chemical properties?
2.
Which property would differ between \( ^{35}Cl \) and \( ^{37}Cl \)?