Compounds, formulae and equations

An element $D\,$ has the following successive ionization energies (in $mol−1\text{kJ~mol}^{-1}$ ):

\text{IE}_1 = 738, \quad \text{IE}_2 = 1451, \quad \text{IE}_3 = 7733, \quad \text{IE}_4 = 10543

Another element $E\,$ is a non-metal with the valence-shell electron configuration $ns^2 np^3$ .

What is the likely formula of the ionic compound formed between $D\,$ and $E$ ?

$D_2E_3$

$D_3E_2$

$D_5E_2$

$D_2E_5$

An element $D\,$ has the following successive ionization energies (in $mol−1\text{kJ~mol}^{-1}$ ):

\text{IE}_1 = 738, \quad \text{IE}_2 = 1451, \quad \text{IE}_3 = 7733, \quad \text{IE}_4 = 10543

Another element $E\,$ is a non-metal with the valence-shell electron configuration $ns^2 np^3$ .

What is the likely formula of the ionic compound formed between $D\,$ and $E$ ?

$D_2E_3$

$D_3E_2$

$D_5E_2$

$D_2E_5$

Compounds, formulae and equations Questions