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Sidana [21]
3 years ago
15

What is the mass number of the isotope lithium-7??

Physics
2 answers:
svp [43]3 years ago
8 0

Explanation:

Mass number is the sum of total number of protons and total number of neutrons present in an atom.  

For example, a neutral atom of lithium has mass number 7 and atomic number 3.

Atomic number means the total number of protons present in an atom.

So, isotope of lithium-7 will have 3 protons and 4 neutrons. Thus, mass number of lithium-7 will be 3 + 4 = 7.

FromTheMoon [43]3 years ago
5 0
Lithium-7 is by far the most-common isotope, making up about 92.5 percent of all natural lithium. A lithium-7 atom contains three protons, four neutrons, and three electrons.
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What is the longest wavelength of light that will emit electrons from a metal whose work function is 3.70 eV
SSSSS [86.1K]

Answer:

h f = Wf + K

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If K = zero then hf = Wf

Wf = h f = h c / λ    or

λ = h c / Wf = 6.63E-34 * 3.0E8 / (3.7 * 1.6E-19)

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2 years ago
Interpretar el servicio de la verdad​
Lelechka [254]
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3 years ago
Part b only please if you have time
andrew-mc [135]
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BUT there's one thing. The given cos(t + pi/6) has nasty extra stuff in it. However, part a gives you a tip on how to relate x and y to a nice clean cos(t)

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i hade the same question

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That's true.

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