All categories

3 years ago

Which of the following statements are True about the experimental process used in the Diels Alder reaction?

Chemistry

1 answer:

vovikov84 [41]3 years ago

8 0

Here we have to get the correct statements among the given, applicable for Diels-Alder reaction.

The true statements in case Diels-Alder reaction are-

1. An excess of Maleic anhydride is used.

2. The I.R. of the products are indistinguishable.

The Diels-Alder reaction is the most is the most important cyclo-addition reaction in organic chemistry. These are addition reactions in which ring systems are formed without eliminating any compounds.

There remains one diene and one dienophile. The reaction is reversible in nature and requires elevated temperature to obtain its transition state. The reaction rate become faster in certain condition like using of polar solvents.

Among the given statements the following statements are true-

1. An excess of maleic anhydride (the most effective di-enophile) is used to process the reaction in forward direction.

2. The products obtain in this reaction are stereoisomers thus are indistinguishable by infrared spectroscopy (IR).

The statements which are not true for the Diels-Alder reaction:

3. The re-crystallization of the products by any polar solvent like methanol is not feasible as it will cause the retro reaction due to stability of the transition state in polar solvent.

4. Cleaning of glassware are compulsory for any reaction it is not specifically true for Diels-Alder reaction.

5. The reaction occurs at elevated temperature thus flame is required.

You might be interested in

Small quantites of hydrogen gas can be prepared in the laboratory by the addition of aqueous hydrochloric acid to metallic zinc.

ira [324]

Answer: The mass or zinc reacted is 0.624 grams.

Explanation:

We are given:

Total pressure = 1.032 atm

Vapor pressure of water = 32 torr = 0.042 atm (Conversion factor: 1 atm = 760 torr)

To calculate partial pressure of hydrogen gas, we use the equation:

$p_{H_2}=p_T-p_{H_2O}\\\\p_{H_2}=1.032-0.042=0.99atm$

To calculate the number of moles of hydrogen gas, we use the equation given by ideal gas follows:

$PV=nRT$

where,

P = pressure of hydrogen gas = 0.99 atm

V = Volume of hydrogen gas = 240. mL = 0.240 L (Conversion factor: 1 L = 1000 mL)

T = Temperature of hydrogen gas = $30^oC=[30+273]K=303K$

R = Gas constant = $0.0821\text{ L. atm }mol^{-1}K^{-1}$

n = number of moles of hydrogen gas = ?

Putting values in above equation, we get:

$0.99atm\times 0.240L=n\times 0.0821\text{ L atm }mol^{-1}K^{-1}\times 303K\\n=\frac{0.99\times 0.240}{0.0821\times 303}=9.55\times 10^{-3}mol$

The chemical equation for the reaction of zinc and hydrochloric acid follows:

$Zn+2HCl\rightarrow ZnCl_2+H_2$

By Stoichiometry of the reaction:

1 mole of hydrogen gas is produced from 1 mole of zinc metal

So, $9.55\times 10^{-3}mol$ of hydrogen gas is produced from = $\frac{1}{1}\times 9.55\times 10^{-3}=9.55\times 10^{-3}mol$ of zinc metal

To calculate the mass of zinc metal, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Molar mass of zinc = 65.38 g/mol

Moles of zinc = $9.55\times 10^{-3}$ moles

Putting values in above equation, we get:

$9.55\times 10^{-3}mol=\frac{\text{Mass of zinc}}{65.38g/mol}\\\\\text{Mass of zinc}=(9.55\times 10^{-3}mol\times 65.38g/mol)=0.624g$

Hence, the mass or zinc reacted is 0.624 grams.

4 0

4 years ago

Use the Earth's Energy Budget diagram to answer the question. Based on the diagram, less solar energy that reaches Earth is ____

Ivan

absorbed, radiated
Hope this helps.

5 0

3 years ago

How do you solve for the Atomic Mass in chemistry?

loris [4]

Https://www.google.com/search?q=how+to+solve+fir+atomic+mass+in+chemisty&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari#kpvalbx=1
Here is the link to a great video that explains your question nicely, hope this helps.

6 0

4 years ago

Read 2 more answers

1. Aluminium reacts with chlorine to produce aluminium chloride. The balanced reaction is:

Anton [14]

Answer:

Explanation:

6 0

3 years ago

Hydrogen gas is filled in a 224 ml glass container at 0 degree celcius and 1 atmospheric pressure. What are the number of molecu

Step2247 [10]

Answer:

$\boxed{\text{6.02 $\math{\times 10^{21}}$ molecules}}$

Explanation:

A pressure of 1 atm and a temperature of 0 °C is the old definition of STP. Under these conditions, 1 mol of a gas occupies 22.4 L.

1. Calculate the moles of hydrogen.

$n = \text{0.224 L} \times \dfrac{\text{1 mol}}{\text{22.4 L}} = \text{0.0100 mol}$

2. Calculate the number of molecules

$\text{No. of molecules} = \text{0.0100 mol} \times \dfrac{\text{6.022 $\times 10^{23}$ molecules}}{\text{1 mol}}\\\\= \textbf{6.02 $\mathbf{\times 10^{21}}$ molecules}\\\\\text{The sample contains }\boxed{\textbf{6.02 $\mathbf{\times 10^{21}}$ molecules}}$

8 0

3 years ago

Read 2 more answers