a) Alkali metals
=> group 1
=> Li: 1s2 2s => 1s
Na: [Ne] 3s => 3s
K: [Ar] 4s => 4s
Rb: [Kr] 5s => 5s
Cs: [Xe] 6s => 6s
Fr: [Rn] 7s => 7s
=> outer electron configuration is ns, where n is the main energy level: 1, 2, 3, 4, 5, 6,7.
b) Alkaline earth metals
=> group 2 => you have to add 1 electron to the alkaly metal of the same row.
=> Be: [He] 2s2 => 2s2
Mg: [Ne] 3s2 => 3s2
Ca: [Ar] 4s2 => 4s2
Sr: [Kr] 5s2 => 5s2
Ba: [Xe] 6s2 => 6s2
Ra: [Rn[ 7s2 => 7s2
=>outer electron configuration is n s2, where n is the main energy level: 1, 2, 3, 4, 5, 6, 7
c) halogens
=> group 7
=> F: [He] 2s2 2p5 => 2s2 2p5
Cl: [Ne] 3s2 3p5 => 3s2 3p5
Br: [Ar] 3d10 4s2 4p5 => 4s2 4p5
I: [Kr] 4d10 5s2 5p6 => 5s2 5p5
At: [Xe] 4f14 5d10 6s2 6p5
=> outer electron configuration is ns2 np5, where n is the main energy level 1, 2, 3, 4, 5, 6, 7
d) Noble gases
=> group 8
I will show only the outer shell which is what is requested
=> He: 1s2
Ne: ... 2s2 2p6
Ar: ... 3s2 3p6
Kr: ... 4s2 4p6
Xe: ... 5s2 5p6
Rn: ... 6s2 6p6
=> the outer electron configuration is ns2 np6, except for He for which it is 1s2
Avogadro's number tells you that in one mol of element (sulfur) there are 6.022x10^23 atoms...
So,
1 mol : 6.022x10^23 = x mol : 1.2x10^2
x = 1.99 x 10^-22 mol
*Although this should be correct, you might want to check your question again. You probably misinterpret the question... you want 1.2x10^23 !! :) check it.
Answer:
Surface tension
Explanation:
A water strider (water bug) is able to walk on water because of water’s Surface tension.
Surface tension is phenomenon in which in liquid where it shrinks itself to its minimum surface area possible, it is very much visible in water surface because of high attraction between the water molecule.
Hey it's me again haha!
the answer to your question is:
answer: so f=20.1
a=8.2
m=?
f=ma
20.1 = 8.2*m in
20.1/8.2=m
so the answer is around 2.45 something!
also i'm sorry this question had be stumbled!
6,200,0 is the answer to that
