This is how fluorine appears in the periodic table.

A green box has F at the center and 9 above. Below it says fluorine and below that 19.00. A blue arrow points to 9.

What information does "9” give about an atom of fluorine? Select three options.

the atomic number
the atomic mass
the number of protons
the number of electrons
the number of neutrons

alfred von schlieffen, german army chief of staff, was given instructions to devise a strategy that would be able to counter a joint attack. in december, 1905, he began circulating what later became known as the schlieffen plan. schlieffen argued that if war took place it was vital that france was speedily defeated.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.