13.8g element consist 4.6 ×10^22 atoms what is atomic mass of element?​

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

What is the mass of 0.46 mol of mgcl2

The identities of substances are the same before and after which type of change