All categories

3 years ago

1.Consider the molecule azulene and

Chemistry

2 answers:

earnstyle [38]3 years ago

6 0

Answer:

b is right answer

Explanation:

estimate pi electron binding energry with in the huckel apporoximation

RSB [31]3 years ago

3 0

Mark Brainliest please

Answer :

The Hückel approximation is used to determine the energies and shapes of the π
π
molecular orbitals in conjugated systems. Within the Hückel approximation, the covalent bonding in these hydrocarbones can be separated into two independent "frameworks": the σ
σ
-bonding framework and the the σ
σ
-bonding framework. The wavefunctions used to describe the bonding orbitals in each framework results from different combinations of atomic orbitals. The method limits itself to addressing conjugated hydrocarbons and specifically only π
π
electron molecular orbitals are included because these determine the general properties of these molecules; the sigma electrons are ignored. This is referred to as sigma-pi separability and is justified by the orthogonality of σ
σ
and π
π
orbitals in planar molecules. For this reason, the Hückel method is limited to planar systems. Hückel approximation assumes that the electrons in the π
π
bonds “feel” an electrostatic potential due to the entire σ
σ
-bonding framework in the molecule (i.e. it focuses only on the formation of π
π
bonds, given that the σ
σ
bonding framework has already been formed).

You might be interested in

An excited ozone molecule, O3*, in the atmosphere can undergo one of the following reactions,O3* → O3 (1) fluorescenceO3* → O +

Maurinko [17]

Answer:

The simplified expression for the fraction is $\text {X} = \dfrac{ {k_3 \times cM} }{k_1 +k_2 + k_3 }$

Explanation:

From the given information:

O3* → O3 (1) fluorescence

O + O2 (2) decomposition

O3* + M → O3 + M (3) deactivation

The rate of fluorescence = rate of constant (k₁) × Concentration of reactant (cO)

The rate of decomposition is = k₂ × cO

The rate of deactivation = k₃ × cO × cM

where cM is the concentration of the inert molecule

The fraction (X) of ozone molecules undergoing deactivation in terms of the rate constants can be expressed by using the formula:

$\text {X} = \dfrac{ \text {rate of deactivation} }{ \text {(rate of fluorescence) +(rate of decomposition) + (rate of deactivation) } } }$

$\text {X} = \dfrac{ {k_3 \times cO \times cM} }{ {(k_1 \times cO) +(k_2 \times cO) + (k_3 \times cO \times cM) } }$

$\text {X} = \dfrac{ {k_3 \times cO \times cM} }{cO (k_1 +k_2 + k_3 \times cM) }$

$\text {X} = \dfrac{ {k_3 \times cM} }{k_1 +k_2 + k_3 }$ since cM is the concentration of the inert molecule

7 0

4 years ago

Please help will give brainliest and brainly points tyty <3

Tanya [424]

Answer:

Convection

Explanation:

3 0

3 years ago

Read 2 more answers

A first order reaction has rate constants of 4.6 x 10-2 s-1 and 8.1 x 10-2 s-1 at 0ºC and 20ºC, respectively. What is the value

Airida [17]

Answer:

D. 18,800 J/mol

Explanation:

We need to use the Arrhenius equation to solve for this problem:

$k=Ae^{\frac{-E_a}{RT}$ , where k is the rate constant, A is the frequency factor, $E_a$ is the activation energy, R is the gas constant, and T is the temperature in Kelvins.

We want to find the value of $E_a$ , so let's plug some of the information we have into the equation. The gas constant we can use here is 8.31 J/mol-K.

At 0°C, which is 0 + 273 = 273 Kelvins, the rate constant k is $4.6*10^{-2}$ . So:

$k=Ae^{\frac{-E_a}{RT}$

$4.6*10^{-2}=Ae^{\frac{-E_a}{8.31*273}$

At 20°C, which is 20 + 273 = 293 Kelvins, the rate constant k is $8.1*10^{-2}$ . So:

$k=Ae^{\frac{-E_a}{RT}$

$8.1*10^{-2}=Ae^{\frac{-E_a}{8.31*293}$

We now have two equations and two variables to solve for. We just want to find Ea, so let's write the first equation for A in terms of Ea:

$4.6*10^{-2}=Ae^{\frac{-E_a}{8.31*273}$

$A=\frac{4.6*10^{-2}}{e^{\frac{-E_a}{8.31*273}} }$

Plug this in for A in the second equation:

$8.1*10^{-2}=Ae^{\frac{-E_a}{8.31*293}$

$8.1*10^{-2}=\frac{4.6*10^{-2}}{e^{\frac{-E_a}{8.31*273}} }e^{\frac{-E_a}{8.31*293}$

After some troublesome manipulation, the answer should come down to be approximately:

Ea = 18,800 J/mol

The answer is thus D.

5 0

3 years ago

Identify the spectator ions in the following molecular equation.

SOVA2 [1]

We can rewrite the equation KBr(aq) + AgNO3(aq) → AgBr(s) + KNO3(aq) into its net ionic equation into
K+ + Br- + Ag + + NO3- = AgBr + K + NO3-only aqueous solutions can dissociate. Spectator ions are present in both sides, hence these are K+ and NO3-. THe rules of assigning oxidation numbers is to identify the number of valence electrons of elements and may be arbitrary depending on the charge of the molecule.

3 0

4 years ago

What should u use to get rid of pimples +rash??

makvit [3.9K]

Aloe the plant helps alot leave it on over night

8 0

3 years ago

Read 2 more answers