a)
→ 
b)
→ 
<h3>
What are half-reactions?</h3>
The half-reaction method is a way to balance redox reactions. It involves breaking the overall equation down into an oxidation part and a reduction part.
a)
→ 

= 
= -0.83 - (-2.71) =1.88V
b)
→ 
= 
=-0. - (0.8) =-0.8V
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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
Answer:
⇒D_AB= 1.21×10^(-9)
Explanation:
Wike chang equation is given as:

Where
D_AB= diffusivity of chlorine in water
Φ= 2.26 for water as solvent
ν= 0.0484 for chlorine as solute
M_B = Molecular weight of water
τ= temperature=289 K
μ= viscosity = 1.1×10^{-3}
Now putting these values in the above equation we get

⇒D_AB= 1.21×10^(-9)
Answer:
Sodium was first discovered in Britain in 1807, where a chemist named Sir Humphry Davy found it by electrolysis of caustic soda.
Explanation:
Hope this helped!
Calculate the number of molecules present in 3.50 mol feo2. 2.11 x 1024 molecules 2.107 x 1023 molecules 3.50 x 1023 molecules <u>3.5*(6.02*10^23)=2.107*10^24 molecules</u>
<h3>What is
molecules?</h3>
A molecule is the smallest unit of a substance that keeps its content and properties. It is made up of two or more atoms that are joined together by chemical bonds. Chemistry is built on molecules. The element symbol and a subscript indicating the number of atoms are used to identify molecules.
The fundamental building block of an element is an atom. They are made up of an electron-surrounded nucleus. An atom is considered to have valence electrons if its electron shell is not completely complete. A chemical (covalent) connection is created and a lower energy state is entered when two or more atoms join forces to share outer shell valence electrons. In an exothermic reaction, energy is released as atoms bond.
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