In several cases, the reaction of di- or trialkyl phosphites with a nucleophilic carbonyl or alkene C may occur without catalyst. In addition to previously described ultrasound or MW-assisted methods, many aromatic aldehydes have been shown to react either with di or tri-alkyl phosphites to fo...
Why does the temperature increase in the stratosphere? Why does the temperature decrease in the troposphere? Why does temperature decrease with higher altitude? Why does it feel cold in the exosphere? Why does all weather occur in the troposphere? Why is the troposphere thicker at the equator?
Why is the main role of the external ear described as air conduction instead of sound conduction? Why would an infection that fills the middle ear with liquid cause the hearing (i.e. the wave signal transmission (WST)) to be affected in a negative manner? How do you think it would affe...
The Mpemba effect is the name given to the assertion that it is quicker to cool water to a given temperature when the initial temperature is higher. This assertion seems counter-intuitive and yet references to the effect go back at least to the writings
Conduction If you touch a hot item, heat flows straight into your body, because there’s a direct connection between you and the hot item. Touch or physical contact is the major base for heat flow throughconduction. Convection Heat flow through convection, on the other hand, can occur withou...
Why does temperature affect heart rate in ectothermic organisms? Why doesn't thermal stratification occur in the atmosphere? Why does gas have the most kinetic energy? How does heat move from one place to another in the troposphere? What causes the sidewalk to heat up? Explain. How do conv...
Explain how water can transfer energy by conduction and by convection. Why does freezing of water not occur at 0 degree C when foreign ions are present? What is the relationship between Entropy and The Second Law of Thermodynamics? In very humid climates where there are numerous b...
Why can gases and liquids both transmit heat by convection? How does solar energy create convection currents? Why is convection more important than conduction in the troposphere? What does Bernoulli's principle explain? How does Bernoulli's principle work? Explain how changes in the state of water...
How does sound travel differently through solids, liquids and gases? Why does sound travel faster in solids? How does the ear work? Why is the main role of the external ear described as air conduction instead of sound conduction? Why does sound travel faster in lowe...
A covalent bond is formed by sharing electrons mutually between two or more atoms. In order to complete the octet of each element, the electrons are shared between the individual atoms to form a covalent bond. A water molecule is an example of a covalent bond....