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3 years ago

Predict the number of peaks that you would expect in the proton-decoupled 13C spectrum of each comound.

Chemistry

1 answer:

dangina [55]3 years ago

4 0

Answer:

To interpret a 13C-NMR spectrum we will use some standards very simple. A 13C-NMR spectrum gives us the following information:

1. Indicates the number of non-equivalent carbons in the molecule.

2. Measuring the chemical shift we can intuit the environment

electronic and determine the next functional groups.

3. In this case we cannot count on integration since the different

carbons have different relaxation times.

The number of peaks in the spectrum indicates the number of types of carbon present in the analyzed substance.

The factors that influence the chemical shift of the signals in the 13C NMR are:

electronegativity of carbon bound groups
carbon hybridization

Explanation:

The nuclear magnetic resonance of C13 is complementary to that of H1. This technique is used to determine the magnetic environment of carbon atoms.

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Draw a line-bond structure for CBrN. Explicitly draw all H atoms. You do not have to include lone pairs in your answer. In cases

DochEvi [55]

Answer:

Br - C ≡ N

Explanation:

To draw the Lewis line-bond structure we need to bear in mind the octet rule, which states that in order to gain stability each <em>atom tends to share electrons until it has 8 electrons in its valence shell</em>.

C has 4 e⁻ in its valence shell so it will form 4 covalent bonds.

Br has 7 e⁻ in its valence shell so it will form 1 covalent bond.

N has 5 e⁻ in its valence shell so it will form 3 covalent bonds.

The most stable structure that respects these premises is:

Br - C ≡ N

It does not have any H atom.

8 0

3 years ago

A scientist exam in two atoms. One has a nucleus with five protons in five neutron surrounded by five electrons. The other has a

grigory [225]

Answer:

C) They are not made of matter.

Explanation:

Case in which protons are inside of neutrons doesn't exist.

8 0

3 years ago

.One ballon is filled with Hydrogen (H2) gas, the other balloon is filled with methane (CH4). Both balloons have the same temper

Neko [114]

Answer:

C. The balloon with CH4 has the same moles of gas molecules as the balloon with H2

Explanation:

Based on combined gas law, gases under the same pressure, temperature and volume have the same number of moles. With this information we can say the rigth statement is:

<h3>C. The balloon with CH4 has the same moles of gas molecules as the balloon with H2</h3>

7 0

3 years ago

How many sigma bonds does NBr3 have?

Kisachek [45]

Answer:

It has 3 sigma bonds

Explanation:

A sigma bond is a covalent interaction between two atoms, these bonds are the strongest type of covalent bonds and they are formed by the overlap of atomic orbitals.

The nitrogen is bond to the bromine atoms through sigma bonds, which means that exist 3 sigma bonds in the molecule.

this molecule has a trigonal pyramid geometry due to the free pair of nitrogen electrons.

5 0

3 years ago

An equilibrium mixture of PCl 5 ( g ) , PCl 3 ( g ) , and Cl 2 ( g ) has partial pressures of 217.0 Torr, 13.2 Torr, and 13.2 To

antoniya [11.8K]

Answer: The new partial pressures of $PCl_5,PCl_3\text{ and }Cl_2$ when equilibrium is re-established are 223.4 torr, 6.82 torr and 26.4 torr respectively.

Explanation:

For the given chemical reaction:

$PCl_3(g)+Cl_2(g)\rightleftharpoons PCl_5(g)$

The expression of $K_p$ for above reaction follows:

$K_p=\frac{P_{PCl_5}}{P_{PCl_3}\times P_{Cl_2}}$ ........(1)

We are given:

$P_{PCl_5}=217.0torr$

$P_{PCl_3}=13.2torr$

$P_{Cl_2}=13.2torr$

Putting values in above equation, we get:

$K_p=\frac{217.0}{13.2\times 13.2}\\\\K_p=1.24$

Now we have to calculate the new partial pressure of $Cl_2$ .

$P_{PCl_5}+P_{PCl_3}+P_{Cl_2}=P_{Total}$

$217.0torr+13.2torr+P_{Cl_2}=263.0torr$

$P_{Cl_2}=32.8torr$

The reaction is re-established and proceed to right direction by Le-Chatelier's principle to cancel the effect of addition of $Cl_2$ .

Now, the equilibrium is shifting to the reactant side. The equation follows:

$PCl_3(g)+Cl_2(g)\rightleftharpoons PCl_5(g)$

Initial: 13.2 32.8 217.0

At eqm: 13.2-x 32.8-x 217.0+x

Putting values in expression 1, we get:

$1.24=\frac{(217.0+x)}{(13.2-x)(32.8-x)}\\\\x=40.4,6.38$

Neglecting the 40.4 value of 'x' because pressure can not be more than initial partial pressure.

Thus, the value of 'x' will be, 6.38 torr.

Now we have to calculate the new partial pressures after equilibrium is reestablished.

Partial pressure of $PCl_5$ = (217.0+x) = (217.0+6.38) = 223.4 torr

Partial pressure of $PCl_3$ = (13.2-x) = (13.2-6.38) = 6.82 torr

Partial pressure of $Cl_2$ = (32.8-x) = (32.8-6.38) = 26.4 torr

Hence, the new partial pressures of $PCl_5,PCl_3\text{ and }Cl_2$ when equilibrium is re-established are 223.4 torr, 6.82 torr and 26.4 torr respectively.

7 0

3 years ago