Which of the following statements are true? (a) Si can form an ion with six fluorine atoms,

Question:

Which of the following statements are true?
(a) Si can form an ion with six fluorine atoms, SiF₆^2-, whereas carbon cannot.
(b) Si can form three stable compounds containing two Si atoms each, Si₂H₂, Si₂H₄, and Si₂H₆.
(c) In HNO₃ and H₃PO₄ the central atoms, N and P, have different oxidation states.
(d) S is more electronegative than Se.