Question

Which has highest specific charge?

• A. $N{a}^{+}(massno=23)$
• B. $M{g}^{2+}(massno=24)$
• C. $A{l}^{+3}(massno=27)$
• D. $S{i}^{+4}(massno=28)$

Answer 1

The correct option is D $S{i}^{+4}(massno=28)$

Specific charge in the ratio of charge of ion to its mass.

Specific charge $=\frac{e}{M}$

For ${Na}^{+}=\frac{e}{23},$ for ${Mg}^{2+}=\frac{2\times e}{24}$

For ${Al}^{3+}=\frac{3\times e}{27},$ for ${Si}^{4+}=\frac{4\times e}{28}$

In is in the following order,

${Si}^{4+}>{Al}^{3+}>{Mg}^{2+}>{Na}^{+}$