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2 years ago

Which electron configuration represents the electrons of an atom in an excited state? * 2-3 2-7-1 2-8 2-8-1

Chemistry

1 answer:

Lemur [1.5K]2 years ago

8 0

2-7-1

<h3>Further explanation </h3>

Electrons can move the shell up or down by releasing energy or absorbing energy

Excited electrons show higher electron transfer to the shell by absorbing energy

So it can be concluded that there are 2 conditions:

Ground state is the state of electrons filling shell with the lowest energy levels.

Excited state is the state of electrons which occupies a higher energy level

The state of excited electrons can be seen from the presence of electrons which do not fill the skin completely but fill the skin afterward

2-7-1

From its 8 electron configuration, filling 3 shells, 2 electrons in the firs shell, 7 electrons in the second shell and 1 electron in the third shell

the electrons in the third shell should fill the electrons in the second shell first according to Aufbau rule (lower energy shells)

$\tt 1s^22s^22p^4\rightarrow ground~state\\\\1s^22s^22p^33s^1\rightarrow excited~state$

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Select correct examples of linear molecules for five electron groups. Select correct examples of linear molecules for five elect

Shalnov [3]

Explanation:

Formula to calculate hybridization is as follows.

Hybridization = $\frac{1}{2}[V+N-C+A]$

where,

V = number of valence electrons present in central atom

N = number of monovalent atoms bonded to central atom

C = charge of cation

A = charge of anion

So, hybridization of $BeCl_{2}$ is as follows.

Hybridization = $\frac{1}{2}[V + N - C + A]$

= $\frac{1}{2}[2 + 2]$

= 2

Hybridization of $BeCl_{2}$ is sp. Therefore, $BeCl_{2}$ is a linear molecule. There will be only two electron groups through which Be is attached.

Similarly, hybridization of $XeF_{2}$ is calculated as follows.

Hybridization = $\frac{1}{2}[V + N - C + A]$

= $\frac{1}{2}[8 + 2]$

= 5

Therefore, hybridization of $XeF_{2}$ is $sp^{3}d. Therefore, [tex]XeF_{2}$ is also a linear molecule. Though there are three lone pair of electrons present on a xenon atom and it is further attached with fluorine atoms through two electron pairs. Hence, there are in total five electron groups.

Thus, we can conclude that out of the given options $XeF_{2}$ is the correct examples of linear molecules for five electron groups.

7 0

2 years ago

Consider the reaction below for which K = 78.2 atm-1. A(g) + B(g) ↔ C(g) Assume that 0.386 mol C(g) is placed in the cylinder re

borishaifa [10]

Answer:

1.65 L

Explanation:

The equation for the reaction is given as:

A + B ⇄ C

where;

numbers of moles = 0.386 mol C (g)

Volume = 7.29 L

Molar concentration of C = $\frac{0.386}{7.29}$

= 0.053 M

A + B ⇄ C

Initial 0 0 0.530

Change +x +x - x

Equilibrium x x (0.0530 - x)

$K = \frac{[C]}{[A][B]}$

where

K is given as ; 78.2 atm-1.

So, we have:

$78.2=\frac{[0.0530-x]}{[x][x]}$

$78.2= \frac{(0.0530-x)}{(x^2)}$

$78.2x^2= 0.0530-x$

$78.2x^2+x-0.0530=0$

Using quadratic formula;

$\frac{-b+/-\sqrt{b^2-4ac} }{2a}$

where; a = 78.2 ; b = 1 ; c= - 0.0530

= $\frac{-b+\sqrt{b^2-4ac} }{2a}$ or $\frac{-b-\sqrt{b^2-4ac} }{2a}$

= $\frac{-(1)+\sqrt{(1)^2-4(78.2)(-0.0530)} }{2(78.2)}$ or $\frac{-(1)-\sqrt{(1)^2-4(78.2)(-0.0530)} }{2(78.2)}$

= 0.0204 or -0.0332

Going by the positive value; we have:

x = 0.0204

[A] = 0.0204

[B] = 0.0204

[C] = 0.0530 - x

= 0.0530 - 0.0204

= 0.0326

Total number of moles at equilibrium = 0.0204 + 0.0204 + 0.0326

= 0.0734

Finally, we can calculate the volume of the cylinder at equilibrium using the ideal gas; PV =nRT

if we make V the subject of the formula; we have:

$V = \frac{nRT}{P}$

where;

P (pressure) = 1 atm

n (number of moles) = 0.0734 mole

R (rate constant) = 0.0821 L-atm/mol-K

T = 273.15 K (fixed constant temperature )

V (volume) = ???

$V=\frac{(0.0734*0.0821*273.15)}{(1.00)}$

V = 1.64604

V ≅ 1.65 L

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2 years ago

Why did we change our understanding of where life comes from?

Andru [333]

Answer:

whathappensinthisstory

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2 years ago

Do you think the tectonic plates are still moving today?why?

jek_recluse [69]

Yes, The tectonic plates are always moving and interacting today. The continents are still moving today. Because sometimes of the most dynamic sites of tectonic activity are seafloor spreading zones and giant rift valleys.

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1 year ago

50.0 grams of KCl is dissolved in water to make a 4.00 L

xeze [42]

Answer:0.1677M

Explanation:

Molarity=moles/volume

Number of moles =mass/molar mass

Once you get the number of moles, you apply it to the molarity formula.

8 0

3 years ago

Which electron configuration represents the electrons of an atom in an excited state? * 2-3 2-7-1 2-8 2-8-1​

Which electron configuration represents the electrons of an atom in an excited state? * 2-3 2-7-1 2-8 2-8-1