Argon, atomic number 18, since it is between chlorine and potassium on the Periodic Table of Elements.
Carbon is the element in the same family as lead with atomic number less than sodium.
calciumThe element sulfur's atomic number is 16, so there are 16 protons in its nucleus. The element bromine's atomic number is 35, and there are 35 protons it its nucleus. This means the element will have an atomic number between 16 and 35. Since the question asked which Group 2 element fits in that window, we can go to the periodic table and look down the column of Group 2 elements and find that calcium is the element so described. It has the atomic number 20, and that means 20 protons in its nucleus.Remember that the Groups on the periodic table of elements are the vertical columns, and they range from Group 1 to Group 18. Group 2 elements are the so-called Alkaine Earth metals. A link is provided to the Wikipedia post on the periodic table. Bookmark this one, kids! Each element on the table is a hyperlink to the Wikipedia post on that element. Even the Group numbers are hyperlinks to the post on that Group! It just doesn't get any better that that.
The periodic table is a good reference - check out the atomic number ! Helium - 2 protons, Nitrogen - 7 protons
They have the same number of protons in the nucleus and same number of electrons surrounding the nucleus.
No, in fact, they rarely are equal. There are different forms of the same type of atom. For example, there are three isotopes of Hydrogen, an element that has one proton. Hydrogen-1 has no neutrons. Hydrogen-2 has one neutron. Hydrogen-3 has two neutrons.
Carbon is the element in the same family as lead with atomic number less than sodium.
Chlorine.
The element described is chlorine. It has 7 valence electrons, which is more than oxygen but fewer than neon. Chlorine has 17 protons, more than sodium but fewer than argon.
The element described would be phosphorus. Phosphorus has 5 valence electrons (more than oxygen) and 15 protons (more than sodium but fewer than argon).
The element in question is magnesium. It has 12 protons (more than sodium and less than argon), 2 more valence electrons than oxygen (which has 6), and 8 fewer valence electrons than neon (which has a full valence shell with 8 electrons).
Cl Chlorine
Chlorine
there is no such element
potassium
The vast majority
Neon has 0 valence electrons so it is not possible to have an element with fewer valence electrons. There can, therefore, be no such element.
Neon has 0 valence electrons so it is not possible to have an element with fewer valence electrons. There can, therefore, be no such element.