Answer:
1) Ca: [Ar]4s²
2) Pm: [Xe]6s²4f⁵
Explanation:
1) Ca:
Its atomic number is 20. So it has 20 protons and 20 electrons.
Since it is in the row (period) 4 the noble gas before it is Ar, and the electron configuration is that of Argon whose atomic number is 18.
So, you have two more electrons (20 - 18 = 2) to distribute.
Those two electrons go the the orbital 4s.
Finally, the electron configuration is [Ar] 4s².
2) Pm
The atomic number of Pm is 61, so it has 61 protons and 61 electrons.
Pm is in the row (period) 6. So, the noble gas before Pm is Xe.
The atomic number of Xe is 54.
Therefore, you have to distribute 61 - 54 = 7 electrons on the orbitals 6s and 4f.
The resultant distribution for Pm is: [Xe]6s² 4f⁵.
337.92 moles of Ozone will be produced
1 Oxygen atom is 8 g
1 mole of ozone, O3 = 8 * 3 = 24 g
7.92 * 1024 = 8110.08 g
1 mole = 24 g
? moles = 8110.08 g
? = 337.92 moles
Read more on moles here:
brainly.com/question/15356425
Hope it helps
No, the elements are not always transparent.
<u>Explanation:</u>
The elements become transparent when the light passes through those elements. Transparency is caused because of the transmission and the passing of the light waves through these elements.
But the metals do not become transparent even when the light waves pass through these metals. Metals do not become transparent because the refractive index in them is very big.
Answer: A solution is made by dissolving 27.8 g of nicotine (Molar Mass = 160 g/mol) in 145 g of cyclohexane (C6H12) to form 142 mL of solution. Calculate the mole fraction of the solute and the molarity, respectively, of this solution.
Explanation:
Answer:
8.88 x 10⁻² M/s
Explanation:
The rate of reaction for:
NO(g) + Cl₂ (g) ⇒ 2NOCl(g)
is rate = -ΔNO/Δt = -ΔCl2/Δt = 1/2 ΔNOCl/Δt
so ΔNOCl/Δt = 2 ΔCl2/Δt = 2 x 4.44 × 10⁻² M/s = 8.88 x 10⁻² M/s
In general given a reaction
aA + bB ⇒ cC + dD
rate = -1/a ΔA/Δt = -1/b ΔB/Δt = 1/c ΔC/Δt = 1/d ΔD/Δt
