Question

an ion M+ contains 10 electrons and 12 neutrons what is its atomic no. and mass no. of element M

Answer 1

M⁺ ion is formed by losing one electron from the outermost shell of M element
M⁺→M-1e⁻
10=M-1⇒M=10+1=11
No.of electrons element M coantains=11
Atomic number of M=No .of protons=No.of electrons=11
Since the atomic no. of M is 11,the element M is sodium
Mass no.of sodium=23
∴Mass no.of M=23