2 Answers. The atomic number of francium is 87. The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment.After the discovery of the neutron in 1932, models for a nucleus composed of protons and neutrons were quickly developed by Dmitri Ivanenko and Werner Heisenberg. Francium has the atomic number 87. Choose your element. SURVEY . its 1 valence electron is very far from the nucleus, so little energy is needed to remove it . Find the numbers of protons, neutrons, and electrons. Q. Francium (Fr) has the lowest ionization energy in Group 1 because - answer choices . Francium-87, because it is the protons that define an element, electron number may change and so may neutron number but proton number can't or you get … If the charge is positive, there are more protons than electrons. An isotope of francium has 87 protons, 136 neutrons, and 87 electrons. Question. Francium - 223. There isn't very much of it and it is radioactive, decaying quickly. Alternatively, you can also calculate the atomic number, atomic mass, and charge. Therefore, an atom of francium has 87 protons and 87 electrons. it has the greatest number of protons, so it attracts its electrons the strongest. An ion has an unequal number of protons and electrons. Protons carry a positive electrical change, while electrons are negatively charged, and neutrons are neutral. Atoms are made of protons, neutrons, and electrons. This means that it has 87 each of protons and electrons. Relevance. There are 34 known Isotopes (atoms with varying amounts of neutrons and weight) of Francium. Francium - 136. The atomic number of a sodium atom is 11 and its mass number is 23. Calculate the number of protons, neutrons and electrons it contains. A neutral atom has the same number of protons and electrons (charges cancel each other out). 30 seconds . Francium - 87. The most stable isotope of Francium , number 87, has a mass of 223. There are 34 known isotopes, so the number of neutrons and mass can vary widely. Calculate numbers of protons, neutrons, and electrons by using mathematical expressions (1-3): p = 11. n = 23 - 11 = 12. e = 11 - 0 = 11. it has the smallest number of valence electrons. Francium is an alkali metal, that has one valence electron. Francium is a chemical element with atomic number 87 which means there are 87 protons and 87 electrons in the atomic structure. What is the correct name of the element? Let’s assume that it is the sulfide anion. it has the greatest atomic mass. Tags: Question 11 . Francium - 174. Anonymous. That means that it has 87 protons, 87 electrons and 136 neutrons. Answer Save. 6 years ago. They are equal to 16, 16 and 18, respectively. The chemical symbol for Francium is Fr .