I believe it was John Newlands.
Hope that helped
Answer:
When the excited electron fall back to the lower energy levels the energy is released in the form of radiations.The characteristics bright colors are due to the these emitted radiations. These emitted radiations can be seen if they are fall in the visible region of spectrum
Explanation:
The electron is jumped into higher level and back into lower level by absorbing and releasing the energy.
The process is called excitation and de-excitation.
Excitation:
When the energy is provided to the atom the electrons by absorbing the energy jump to the higher energy levels. This process is called excitation. The amount of energy absorbed by the electron is exactly equal to the energy difference of orbits. For example if electron jumped from K to L it must absorbed the energy which is equal the energy difference of these two level. The excited electron thus move back to lower energy level which is K by releasing the energy because electron can not stay longer in higher energy level and comes to ground state.
De-excitation:
When the excited electron fall back to the lower energy levels the energy is released in the form of radiations. this energy is exactly equal to the energy difference between the orbits. The characteristics bright colors are due to the these emitted radiations. These emitted radiations can be seen if they are fall in the visible region of spectrum
energy can't be created or destroyed, but mass particles can decay or tranform into others as long as the total mass/energy (remeber E=MC2) is conserved, in nuclear reactions one type of sub-atomic particle change into another, this destabilizes the nucleus forcing it to split and release a certain amount of energy in the form of massless particles
Answer:
Mass = 5.92 g
Explanation:
Given data:
Volume of O₂ = 4.15 mol
Temperature and pressure = standard
Mass in gram = ?
Solution:
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
By putting values,
1 atm × 4.15L = n ×0.0821 atm.L /mol.K × 273.15 k
4.15 atm.L = n ×22.43 atm.L /mol
n = 4.15 atm.L / 22.43 atm.L /mol
n = 0.185 mol
Mass in gram:
Mas = number of moles × molar mass
Mass = 0.185 mol ×32g/mol
Mass = 5.92 g
