1. The elements are arranged in order of decreasing atomic numbers in a table called the periodic table.   True   False   2. Atomic number of an element is the number of neutrons present in the nucleus of the atom.   True   False   3. Of a proton, neutron and an electron, the electron is the lightest.   True   False   4. Electrons are present in the nucleus.   True   False   5. Neutrons are negatively-charged.   True   False   6. Electrons revolve around the nucleus in shells or orbits.   True   False   7. The number of electrons in a neutral atom is equal to its atomic number.   True   False