Answer:
So sorry if I was wrong but I think it's B. Because from the source states,
https://socratic.org/questions/which-group-on-the-periodic-table-is-the-least-reactive-why
"The least reactive elements are those who have a full outermost valence shell ie they have 8 electrons in the outer shell so elements such as helium, neon, radon or the transition elements."
Answer:
Displacement is the shortest distance travelled by a moving body through a entire journey.
The work done by the man pushing a fixed wall with the force of 100N is zero
work = force * displacement
Explanation:
Answer:
1.64x10⁻¹⁸ J
Explanation:
By the Bohr model, the electrons surround the nucleus of the atom in shells or levels of energy. Each one has it's energy, and the electron doesn't fall to the nucleus because it can reach another level of energy, and then return to its level.
When the electrons go to another level, it absorbs energy, and then, when return, this energy is released, as a photon (generally as luminous energy). The value of the energy can be calculated by:
E = hc/λ
Where h is the Planck constant (6.626x10⁻³⁴ J.s), c is the light speed (3.00x10⁸ m/s), and λ is the wavelength of the photon.
The wavelength can be calculated by:
1/λ = R*(1/nf² - 1/ni²)
Where R is the Rydberg constant (1.097x10⁷ m⁻¹), nf is the final orbit, and ni the initial orbit. So:
1/λ = 1.097x10⁷ *(1/1² - 1/2²)
1/λ = 8.227x10⁶
λ = 1.215x10⁻⁷ m
So, the energy is:
E = (6.626x10⁻³⁴ * 3.00x10⁸)/(1.215x10⁻⁷)
E = 1.64x10⁻¹⁸ J
Answer:
The number of stamps and cards Maggie has left if she gives 45 stamps to a friend is 183
Explanation:
If Maggie gives 45 stamps to a friend, you must calculate the number of stamps and cards she has left.
You know Maggie has 4 folders with 30 stamps in each folder. So the number of stamps she owns is calculated as:
4 folders*30 stamps in each folder= 120 stamps
If Maggie gives 45 stamps to a friend, then the number of stamps she has left will be calculated as the difference (the subtraction) between the stamps she owned and the ones she gives away:
120 stamps - 45 stamps= 75 stamps
On the other hand, she has 3 binders with 36 baseball cards in each binder. So the number of cards she owns is calculated as:
3 binders * 36 baseball cards in each binders= 108 baseball cards
The number of stamps and cards you have left is calculated as:
75 stamps + 108 baseball cards= 183
<em><u>The number of stamps and cards Maggie has left if she gives 45 stamps to a friend is 183</u></em>
