Answer:
in plant and animal cells
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.
Cholesterol is a sterol, it is a type of lipid molecule, and is biosynthesized by all animal cells. Total cholesterol level lesser than 200 milligrams per deciliter (mg/dL) is considered desirable for an adult. The standard unit used for any substance is gram per liter. However sometimes the concentration can also be expressed in terms of mg per deciliter. In this context 1 gram per liter is equal to 100 milligram per deciliter.
Thus 1.85 gram per liter is equal to 185 mg per deciliter. So 1.85 g/L is equivalent to 185mg per deciliter.
Answer:
A scientist is studying a shock wave from an earthquake, he is studying mechanical wave.
Explanation:
The shock waves are experienced during earthquake. At the area of increased pressure shock wave are created as the object in that places moves faster as compared to the speed of sound. Shock wave are type of mechanical wave. For its transfer it requires a medium. An electromagnetic wave can travel of its own without any medium, under electromagnetic wave gamma ray and radio wave comes. they are transverse wave.
<u>Answer:</u> The temperature of the system is 273 K
<u>Explanation:</u>
To calculate the number of moles, we use the equation:
Given mass of carbon dioxide = 1 lb = 453.6 g (Conversion factor: 1 lb = 453.6 g)
Molar mass of carbon dioxide = 44 g/mol
Putting values in above equation, we get:

To calculate the temperature of gas, we use the equation given by ideal gas equation:
PV = nRT
where,
P = Pressure of carbon dioxide = 200 psia = 13.6 atm (Conversion factor: 1 psia = 0.068 atm)
V = Volume of carbon dioxide =
(Conversion factor:
)
n = number of moles of carbon dioxide = 10.31 mol
R = Gas constant = 
T = temperature of the system = ?
Putting values in above equation, we get:

Hence, the temperature of the system is 273 K