<span>The amount of
protons is equal to the number of electrons of a chemical element. The atomic
number of an element also determines the number of the protons it contains.
The number of protons is also the same number of electrons. Protons are positively charged, electrons are
negatively charged. To get the number of neutrons, all you need is to deduct
the number of the atomic mass or mass number from the atomic number. Potassium has 19
protons, therefore has 19 electrons as well. The atomic mass of Potassium is
39. So, the number of neutrons Potassium has is 20. </span>
Potassium
Atomic
number: 19
Protons: 19
Electrons: 19
Atomic Mass:
39
Neutron: 20
Nitrogen
Atomic
number: 7
Protons: 7
Electrons: 7
Atomic Mass:
14.007
Neutrons: 7
Oxygen
Atomic
Number: 8
Protons: 8
Electrons: 8
Atomic Mass:
15.99
Neutrons: 8
The wavelength is obtained as 122 nm. Option A
<h3>What is the wavelength?</h3>
We know that from the Bohr model of the atom, an electron can move from a higher energy level to a lower energy level or from a lower energy level to a higher energy level. This is the idea of energy quantization as put forward by Neill Bohr.
The wavelength can be obtained by the use of the formula;
1/λ = RH(1/n^2initial - 1/n^2 final)
λ = wavelength of the emitted light
RH = Rydberg's constant
n intial = initial energy level
nfinal = final energy level
Thus;
1/λ = 1.09 * 10^7(1/1^2 - 1/2^2)
1/λ = 1.09 * 10^7( 1 - 0.25)
λ = 122 nm
Learn more about the wavelength:brainly.com/question/13533093
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Answer:
<h2>
Red</h2>
Explanation:
Red is diffracted the most due to its long wavelength. Compared to violet which is the shortest and is diffracted the least.
Answer: 
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
The balanced chemical equation when when aqueous solutions of chromium(III) sulfate and calcium nitrate are combined is:
