The table shows the successive ionisation energies of an element X. Ionisation energies / $\text{kJ mol}^{-1}$: 1st = 950, 2nd = 1800, 3rd = 2700, 4th = 4800, 5th = 6000, 6th = 12300. Which formula might a chloride of X have?
- A$\text{XCl}$
- B$\text{XCl}_2$
- C$\text{XCl}_3$
- D$\text{XCl}_4$