<span>Throughout the development of particle physics, scientists have created different models to understand the atom. When we are talking about the diameter of an atom, we would refer to the Bohr radius, which is the radius from the nucleus to the orbiting electron.
In this case, a hydrogen atom has one electron, and the Bohr radius in the ground state is 5.29 x 10^{-11} meters. To find the diameter, we just multiply the Bohr radius by 2.
diameter = 2 x 5.29 x 10^{-11} meters
diameter = 10.58 x 10^{-11} meters
diameter = 1.058 x 10^{-10} meters
The diameter of a hydrogen atom in ground state is:
1.058 x 10^{-10} meters</span>
Answer:
A = shielding.
Explanation:
The addition of electron causes the atomic size increase from top to bottom due to increase in atomic number.
As the atomic number increased one more electron is added and because of this electron on more electronic shell is added. Thus the electron become more away from the nucleus as many of other electrons are present in the way from nucleus to the outer electrons.
The hold of nucleus becomes weaker. Although nuclear charge is also increased but at the same time other electrons shield the respective electrons. So effective nuclear charge is weaker than the actual nuclear charge.
Because of this shielding it is easy to remove the electrons or we can say ionization energy decreases.
Explanation:
(a) The mass of an object remains the same always. It is independent of its location. In this case, an iron nail is ground into powder. It means that its mass will remain unchanged. Hence, (a) is the correct option.
(b) Whenever there is a change of color of an object, a chemical reaction occurs. It shows that a reaction happens there. In this problem, a paper turns yellow-brown upon exposure to sunlight. A chemical reaction takes place there. Hence, (b) is the correct option.
Answer:
Explanation:To find the number of moles of solute in a volume of a solution, we need to multiply volume by concentration. BUT we also need to check that the units are the same. Molarity (M) is moles per liter, so we need to convert 250mL to L.
250mL=0.250L
Now we can multiply the concentration by volume.
0.4M*0.250L