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.
        
             
        
        
        
Answer:
The wavelength for the transition from n = 4 to n = 2 is<u> 486nm</u> and the name  name given to the spectroscopic series belongs to <u>The Balmer series.</u>
Explanation
lets calculate -
 Rydberg equation-   
where , is wavelength , R is Rydberg constant (
 is wavelength , R is Rydberg constant (  ),
),  and
 and  are the quantum numbers of the energy levels. (where
are the quantum numbers of the energy levels. (where  )
)
Now putting the given values in the equation,
                 

     Wavelength 
              = = 486nm
 = 486nm
 <u>    Therefore , the wavelength is 486nm and it belongs to The Balmer series.</u>
 
        
             
        
        
        
Answer:
0.39760273
Explanation:
I typed into calculator hope it's right.
 
        
             
        
        
        
Answer:
24.87× 10²³ atoms of Ni
Explanation:
Given data:
Number of atoms of Ni= ?
Number of moles of Ni = 4.13 mol
Solution:
we will calculate the number of atoms of Ni by using  Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
 1 mole = 6.022 × 10²³ atoms
4.13 mol ×  6.022 × 10²³ atoms /1 mol 
24.87× 10²³ atoms of Ni
 
        
             
        
        
        
Answer:
C:to the right side of the periodic table, and it is given
the suffix -ide.