Question

State the name and mass number of the isotope relative to which all atomic masses are measured?

a. Carbon-12 (¹²C)
b. Hydrogen-1 (¹H)
c. Oxygen-16 (¹⁶O)
d. Uranium-238 (²³⁸U)

Answer 1

The isotope relative to which all atomic masses are measured is carbon-12.

Step-by-step explanation:

The isotope relative to which all atomic masses are measured is carbon-12 (¹²C). Carbon-12 has 6 protons and 6 neutrons, giving it a mass number of 12. Atomic masses of other elements and isotopes are measured relative to the carbon-12 isotope.