Explanation:
A catalyst lowers the activation energy of a reaction allowing them to proceed faster than they would naturally. Activation energy is the free energy that is required to be input in the reactant side to activate them to the transition state after which the reaction proceeds spontaneously to products.
An example of a catalyst is platinum, that is put in the exhaust of cars, to help convert carbon monoxide to carbon dioxide before it is emitted into the air.
Answer: The energy of the 4-s subshell is lower than the energy of 3-d subshell.
Explanation:
During the filling of electrons in subshells, the lower energy levels are filled before the higher energy levels. Also known as Aufbau principle.
Energy of the sublevel = (n + l)
where : n = Principal quantum number
l = Azimuthal quantum number(s=0,p=1,d=2,f=3)
Energy of 4-s subshell= (4+0) = 4
Energy of 3-d subshell=(3+2) = 5
Energy of 4-s subshell is lower than the energy of 3-d subshell, that is why 4s orbital is filled before the 3-d subshell.
Glaciers are found in areas where the net accumulation of snow exceeds the melt, therefore they are usually found in areas of high elevation, cold temperatures, and high precipitation.
Geysers are found in areas of shallow crust with high heat flow, such as hot spots.
Neils bohar proposed his atomic model in 1913.
He describe that's electron travel in a circular orbit surrounds the neuclus of an atom.each orbit has quantized energy and size. Energy is transmitted when an electron jumps from one to other orbit near to nucleus.and it absorb energy when it jumbs away from nucleus.he also said that these electrons are restricted to fixed orbits. In excited state of electron, they absorb or emitt photon with specific wavelength.