Answer:
Initial state Final state
3 ⇒ 2
3 ⇒ 1
2 ⇒ 1
Explanation:
For this exercise we must use Bohr's atomic model
E = - 13.606 / n²
where is the value of 13.606 eV is the energy of the ground state and n is the integer.
The energy acquired by the electron in units of electron volt (eV)
E = e V
E = 12.5 eV
all this energy is used to transfer an electron from the ground state to an excited state
ΔE = 13.6060 (1 / n₀² - 1 / n²)
the ground state has n₀ = 1
ΔE = 13.606 (1 - 1/n²)
1 /n² = 1 - ΔE/13,606
1 / n² = 1 - 12.5 / 13.606
1 / n² = 0.08129
n = √(1 / 0.08129)
n = 3.5
since n is an integer, maximun is
n = 3
because it cannot give more energy than the electron has
From this level there can be transition to reach the base state.
Initial state Final state
3 ⇒ 2
3 ⇒ 1
2 ⇒ 1
Answer: B. CO
Explanation:
Diatomic molecules are those that are formed by two atoms of the same chemical element (homonuclear diatomic molecule) or different chemical element (heteronuclear diatomic molecule).
In this sense, oxygen is a homonuclear diatomic molecule because it is formed by two atoms of the same element (
) and Carbon monoxide (
) is heteronuclear diatomic molecule.
Sodium Chloride 
is not a diatomic molecule because is a product of ionization, but it can be diatomic in its gas phase with a polar covalent bond.
Answer:
Explanation:
Since the block is at rest in an elevated position, we can assume that it only has potential energy.
U=mgh is the formula for potential energy where U=potential energy, m= mass, g=acceleration due to gravity, and h=height.
Plug in known variables....
U=4kg*9.8m/s^2*20m
U=784 joules of potential energy or letter A.
Answer:
I believe the answer is D.
Explanation:
Protons are found inside the nucleus so are neutrons. Electrons are found outside the nucleus.
Their relative speed is the sum of 60 and 40 or 100km/hr. They will travel the 150km in 1.5 hrs. When two object approach each other, the closing speed is just the sum of the speeds, therefore, the closing speed is your case is 100kph. So they will meet in 1.5 hours.
