Strontium is in Group 2. Nitrogen is in Group 5.
Strontium reacts with nitrogen to form the ionic compound strontium nitride.
Which description of a dot and cross diagram for strontium nitride is correct? Only the outer shell electrons are shown on the nitride ions.
1 strontium ion, Sr2+\mathrm{Sr^{2+}}Sr2+, and 2 nitride ions, each N−\mathrm{N^{-}}N− with 8 outer electrons
2 strontium ions, each Sr3+\mathrm{Sr^{3+}}Sr3+, and 3 nitride ions, each N2−\mathrm{N^{2-}}N2− with 8 outer electrons
3 strontium ions, each Sr2+\mathrm{Sr^{2+}}Sr2+, and 2 nitride ions, each N3−\mathrm{N^{3-}}N3− with 5 outer electrons
3 strontium ions, each Sr2+\mathrm{Sr^{2+}}Sr2+, and 2 nitride ions, each N3−\mathrm{N^{3-}}N3− with 8 outer electrons
64 exam-style questions on OCR GCSE Chemistry 2.2 Bonding, covering 2.2.1 Metals, non-metals and the Periodic Table, 2.2.2 Types of chemical bonding and dot and cross diagrams, 2.2.3 Limitations of bonding models, and 2.2.4 Reactivity, atomic number and the modern Periodic Table. Each one has a worked solution and a mark scheme showing where the marks go.