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.
Answer: 2 moles of 
will be formed.
Explanation:
To calculate the moles :
The balanced chemical equation is:
According to stoichiometry :
2 moles of 
give = 2 moles of
Thus 2 moles of give =
of
Thus 2 moles of will be formed.
The molar mass of this gas is 92.3 g/mol
Calculation
By use ideal gas equation PV =nRT where
n=mole p=pressure V= volume R = gas constant T= temperature
n = mass /molar mass(MM)
substitute in the equation
PV =(mass/MM)RT
mass = density x volume(V)
Therefore PV =(density xV/ MM) xRT
divide both side by by V
P= (density/Mm) xRT
making MM the subject of the formula
MM = densityPRT
At STP = P= 1 atm, R= 0.0821 L.atm/Mol.k T = 273 K
MM is therefore = 4.12 g/l x 1 atm x 0.081 L.atm/mol.k x 273 K = 92.3 g/mol
The littoral zone of a lake is the area closest to the shore. It has very little biological activity but includes a lot of oxygen. The water in the lake's littoral zone is freshwater, free of living organisms such as plants and fish.
