Question

If the number of protons in $X^{3-}$ is 56, then the number of electrons in $X^{2+}$ will be:

• A. 47
• B. 54
• C. 38
• D. 59

Answer 1

The correct option is B 54

Given:
Number of protons in $X^{3-}$ = 56
Number of protons remains constant.
In a neutral species,
Number of protons = number of electrons
Number of protons in $X^{2+}$ = 56
$\text{Number of electrons in}{X}^{2+}=\text{Number of electrons in}X-2$
$=56-2$
number of electrons in $X^{2+}$ is $54$.