Answer:
Dysprosium [Dy]=![[Xe]4f^{10}6s^2](https://tex.z-dn.net/?f=%5BXe%5D4f%5E%7B10%7D6s%5E2)
Americium [Am]=![[Rn]5f^77s^2](https://tex.z-dn.net/?f=%5BRn%5D5f%5E77s%5E2)
Dysprosium is a chemical element with symbol Dy and atomic number of 66. It is a rare earth metal and as it contains partially filled f sub shells, it belongs to f block. Xe is the nearest noble gas and has atomic number of 54.
Americium is a chemical element with symbol Am and atomic number of 95. It is a rare earth metal and as it contains half filled f sub shells, it belongs to f block. Radon is the nearest noble gas and has atomic number of 86.
55.8 grams Would be the answer
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>
Answer:
European Union was on grand committee
The formula for the self ionization of water is 2H₂O(l)⇄H₃O⁺(aq)+OH⁻(aq)
The hydronium (H₃O⁺) is usually just referred to as a hydrogen ion or a proton (H⁺) and hydroxide (OH⁻) doesn't have another name that I am aware of. These ions do stay in solution. However the concentrations are really small and the equilibrium constant (K(w)) is 1×10⁻¹⁴.
I hope this helps. Let me know if anything is unclear.
