Question

solve it urgent needs in explaining

not to give option only please

Answer 1

Here e/m ratio indicates the charge/mass ratio.

Charge on He+ = 1 & mass of He+ = 4 → e/m = 1/4

Charge on H⁺ (or ¹H₁⁺) = 1 & mass of H = 1 → e/m = 1

Charge on Be⁺³ = 3 & mass of Be⁺³ = 9 → e/m = 1/3

Charge on Li⁺² = 2 & mass of Li⁺² = 7 → e/m = 2/7

Charge on ²H₁⁺ = 1 & mass of ²H₁⁺ = 2 → e/m = 1/2

Now, based on the above values, option (B) is the correct answer.

∴ The ratio of e/m values of He⁺ and Li⁺² is 7:8

Hope it helps!!