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denis-greek [22]

3 years ago

12

What do the spectral lines represent?

1 answer:

scZoUnD [109]3 years ago

8 0

Question

What do the spectral lines represent?

Answer:

Spectral lines is defined by quantum mechanics in terms of energy levels of ions, molecules, and atoms. When electrons move from a higher level to lower one, photons are emitted and an emission line can be seen in the spectrum. As electrons jump down to the n=2 orbit, they emit photons of specific frequency (hence colour) that can be seen as emission lines in the visible part of spectrum.

Explanation:

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I need the answers to those 2 :) don’t explain just answer :D

Gwar [14]

Answer:

where is the question?

Explanation:

4 0

3 years ago

If 150 g dimethylhydrazine reacts with excess dinitrogen tetroxide and the product gases are collected at 127oC in an evacuated

zhuklara [117]

Answer : The the partial pressure of the nitrogen gas is 0.981 atm.

The total pressure in the tank is 2.94 atm.

Explanation :

The balanced chemical reaction will be:

$(CH_3)_2N_2H_2(l)+2N_4O_4(l)\rightarrow 3N_2(g)+4H_2O(g)+2CO_2(g)$

First we have to calculate the moles of dimethylhydrazine.

Mass of dimethylhydrazine = 150 g

Molar mass of dimethylhydrazine =60.104 g/mole

$\text{Moles of dimethylhydrazine}=\frac{\text{Mass of dimethylhydrazine}}{\text{Molar mass of dimethylhydrazine}}$

$\text{Moles of dimethylhydrazine}=\frac{150g}{60.104g/mole}=2.49mole$

Now we have to calculate the moles of $N_2$ gas.

From the balanced chemical reaction we conclude that,

As, 1 mole of $(CH_3)_2N_2H_2$ react to give 3 moles of $N_2$ gas

So, 2.49 mole of $(CH_3)_2N_2H_2$ react to give $2.49\times 3=7.47$ moles of $N_2$ gas

Now we have to calculate the partial pressure of nitrogen gas.

Using ideal gas equation :

$PV=nRT\\\\P_{N_2}=\frac{nRT}{V}$

where,

P = Pressure of $N_2$ gas = ?

V = Volume of $N_2$ gas = 250 L

n = number of moles $N_2$ gas = 7.47 mole

R = Gas constant = $0.0821L.atm/mol.K$

T = Temperature of $N_2$ gas = $127^oC=273+127=400K$

Putting values in above equation, we get:

$P_{N_2}=\frac{(7.47mole)\times (0.0821L.atm/mol.K)\times 400K}{250L}=0.981atm$

Thus, the partial pressure of the nitrogen gas is 0.981 atm.

Now we have to calculate the total pressure in the tank.

Formula used :

$P_{N_2}=X_{N_2}\times P_T$

$P_T=\frac{1}{X_{N_2}}\times P_{N_2}$

$P_T=\frac{1}{(\frac{n_{N_2}}{n_T})}\times P_{N_2}$

$P_T=\frac{n_{T}}{n_{N_2}}\times P_{N_2}$

where,

$P_T$ = total pressure = ?

$P_{N_2}$ = partial pressure of nitrogen gas = 0.981 atm

$n_{N_2}$ = moles of nitrogen gas = 3 mole (from the reaction)

$n_{T}$ = total moles of gas = (3+4+2) = 9 mole (from the reaction)

Now put all the given values in the above formula, we get:

$P_T=\frac{9mole}{3mole}\times 0.981atm=2.94atm$

Thus, the total pressure in the tank is 2.94 atm.

8 0

3 years ago

How many signals would you expect to find in the 1h nmr spectrum of 1 butanol?

guajiro [1.7K]

The ¹H-NMR of 1-Butanol is shown below,

There are Five signals found in the proton NMR spectrum of 1-Butanol.

A Broad Singlet signal at ≈ 4.7 ppm (Down Field = More Deshielded) is for proton directly attached to Oxygen atom.

Triplet Signal at ≈ 3.65 ppm (Down Field = Deshielded) is for methylene group directly attached to Oxygen atom.

Multiplet Signal at ≈ 1.6 ppm is for methylene which is present between two methylene groups. The shielding effect is increasing as moving away from Oxygen atom.

Multiplet Signal at ≈ 1.4 ppm is for methylene which is present between terminal methyl and methylene groups. The shielding effect is increasing as moving away from Oxygen atom.

Triplet Signal at ≈ 0.9 ppm (Up Field = Most Shielded) is for terminal methyl group attached to methylene group.

Result:
Five Signals are found in the ¹H-NMR of 1-Butanol.

4 0

3 years ago

How can we define a virus .

Ghella [55]

<span>metabolically inert, infectious agent that replicates only within the cells of living hosts, mainly bacteria, plants, and animals: composed of an RNA or DNA core, a protein coat, and, in more complex types, a surrounding envelope.</span>

3 0

3 years ago

I have finals help!!!!!

AURORKA [14]

Answer:

C E F G

Explanation:

1s2 2s2 2p2 is carbon element, group 4 so A is false, it is not a noble gas so B is false, P-block elements are from 13 to 18 so carbon is included so C is true, S-block elements are columns 1 and 2 and Helium so carbon not included so D false, it is in period 2 so E true, has 2 energy levels so F true, it is a representative element so G is true

7 0

3 years ago

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