Final answer:
The mass of an electron is 9.11 x 10^-31 kg in scientific notation, a value that is fundamental in physics and chemistry.
Step-by-step explanation:
The mass of the electron in scientific notation is 9.11 × 10-31 kg. This value has been confirmed through various experiments to an incredibly high degree of accuracy. The electron mass is critically important in many calculations in physics and chemistry, making it a fundamental constant in the study of atomic and subatomic particles.