Explanation:
The group number in the periodic table represents number of valence electrons of the elements in a certain group.
Group 1 : 2,8,1
Group 2 : 2,8,8,2
Group 3 : 2,8,3
Group 4: 2,4
Group 7 : 2,8,7
Answer:
The answer to this question is ( a )
Explanation:
First, we need to get the value of Ka:
when Ka = Kw / Kb
we have Kb = 1.8 x 10^-5
and Kw = 3.99 x 10^-16 so, by substitution:
Ka = (3.99 x 10^-16) / (1.8 x 10^-5) = 2.2 x 10^-11
by using the ICE table :
NH4+ + H2O →NH3 + H+
intial 0.013 0 0
change -X +X +X
Equ (0.013-X) X X
when Ka = [NH3][H+] / [NH4+]
by substitution:
2.2 x 10^-11 = X^2 / (0.013 - X) by solving this equation for X
∴X = 5.35 x 10^-7
∴[H+] = X = 5.35 x 10^-7
∴PH = - ㏒[H+]
= -㏒(5.35 x 10^-7)
= 6.27
In metallic bonding, valence electrons of metals move freely between neighbouring atoms. metals are ductile
because the forces that hold their atoms together are weak.
Explanation:
- Metallic bonds are the force which holds atoms together in a metal.
- Valence electrons present in the metals are freely moving between the other neighbouring atoms. The interaction between the positive ions which electrons leave behind and the valence electrons give the binding force which able to hold the metallic crystal together as it is.
- In metals, the electrons are free to travel from one metal to another metal. This speciality is the reason for their electric conductivity. And this shows that the metal-metal bond is weak in metal.
I think it’s A (6), pls give brainliest!
