We call these reactive elements, becausethese atoms really like to follow the buddysystem and form bonds with other atoms.Noble gases, however, don't have thisproblem. Their outer shells are filled to the max, so they don't need to bond or react with any other atoms.
You will need a periodic table to help you answer this problem. The atomic numbers are arrange from lowest to highest in the periodic table. You can locate element number 55 to be Cesium with an atomic weight of 132.905 amu. So, you start from element 56. The following elements are:
56 Barium 137.328 amu
57 Lanthanium 138.905 amu
58 Cerium 140.116 amu
59 <span>Praseodymium 140.908 amu
60 Neodymium 144.243 amu
Neodymium is already greater than 144 amu. Therefore, these elements only include Barium, Lanthanium, Cerium and Praseodymium.</span>
Kilo
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king Hector died by drinking chocolate milk
25 milligrams equal 0.025 grams
It is ionic bond because of Na valency and it is alkali metal and cl is non metal and it’s valency , they both share electron and make ionic bonding .
