Answer: cycloaddition of 1,3-butadiene and allyl anion is thermally allowed.
Explanation:
Using the frontier molecular orbital approach, we consider if the symmetry of the LUMO of the diene (1,3-cyclobutadiene) and the HOMO of the dienophile allyl anion), match each other since the diels alder reaction is a symmetry allowed process. The symmetries of these frontier molecular orbitals match each other hence the reaction is thermally allowed. It should be notes that 4+2 cycloadditions are thermally allowed although they are slow.
What are you asking,
When?
Answer:
1)clinical thermometer has temperature range 35 to 42degree celcius where labouratery thermometer has -10 to 110 degree celcius.
2)clinical thermometer is used to measure body temperature whare labouratory thermometer is not used to measure body temperature
Answer: -
100 grams
Explanation: -
Mass of Oxygen = 40 g
Chemical formula of oxygen gas = O2
Molar mass of oxygen = 16 x 2 = 32 gram
Atomic mass of Mg = 24g
Molar mass of MgO = 24 x 1 + 16 x 1 =40 gram
The balanced chemical equation for the reaction is
2Mg + O2 -- > 2 MgO
So from the balanced equation we see that 1 O2 react to give 2 MgO
32 grams of O2 react to give 2 x 40 gram of MgO
40 grams of O2 react to give 
=100 gram of MgO
According to the kinetic theory, the mean free path is the average distance a single atom or molecule of an element or compound travels with respect with the other atoms during a collision. The greater the mean free path, the more ideal the behavior of a gas molecule is because intermolecular forces are minimum. To understand which factors affect the mean free path, the equation is written below.
l = μ/P * √(πkT/2m), where
l is the mean free path
μ is the viscosity of the fluid
P is the pressure
k is the Boltzmann's constant
T is the absolute temperature
m is the molar mass
So, here are the general effects of the factors on the mean free path:
Mean free path increases when:
1. The fluid is viscous (↑μ)
2. At low pressures (↓P)
3. At high temperatures (↑T)
4. Very light masses (↓m)
The opposite is also true for when the mean free path decreases. Factors that are not found here have little or no effect.