Here we have to compare the Bohr atomic model with electron cloud model.
In the Bohr's atomic model the electrons of an element is assumed to be particle in nature. Which was unable to explain the deBroglie' hypothesis or the uncertainty principle and has certain demerits.
The uncertainty principle reveals the wave nature of the electrons or electron clod model. The Bohr condition of a stable orbits of the electron can nicely be explained by the electron cloud model, the mathematical form of which is λ = nh/mv, where, λ = wavelength, n is the integral number, h = Planck's constant, m = mass of the electron and v = velocity of the electron.
The integral number i.e. n is similar to the mathematical form of Bohr's atomic model, which is mvr = nh/2π. (r = radius of the orbit).
Thus, the electron cloud model is an extension of the Bohr atomic model, which can explain the demerits of the Bohr model. Later it is revealed that the electron have both particle and wave nature. Which is only can explain all the features of the electrons around a nucleus of an element.
Answer:
1.5 moles
Explanation:
To find the number of moles of HCl in 500 mL of a 3 M solution of HCl, we consider moles in 1 liter/ 1000 mL.
3 moles HCl is contained in 1000 mL
x moles is HCl is contained in 500 mL

Hence the number of moles of HCl in 500 mL is 1.5 moles.
Answer:
168.0 g
Explanation:
First thing, write a balanced chemical equation:

n(H2SO4) = concentration * volume
= 1.0 M * 2.0 L
= 2.0 mol
According to the balanced equation, 1 mol of acid requires 2 mol of sodium bicarbonate. This means that 2 mol of acid requires 2 mol of sodium bicarbonate. What mass of sodium bicarbonate is this?
mass (NaHCO3) = number of moles * molar mass
= 2.0 mol * 84.0065 g/mol
= 168.0 g
The position of hydrogen is controversial in periodic table because hydrogen is the only element with out neutron. it belongs to 1 st group but it is not placed there .
The magnitude of the force required to change the length of a spring-like object is directly proportional to the spring constant and the displacement of the spring. Elastic potential energy is directly proportional to the square of the change in length and the spring constant.