Most of the mass of an atom is located in the (nucleus), and most of the volume is taken up by the (electron clouds).
The ones in the parenthesis are your answers.
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Answer:
4
Explanation:
Relationship between wavenumber and Rydberg constant (R) is as follows:

Here, Z is atomic number.
R=109677 cm^-1
Wavenumber is related with wavelength as follows:
wavenumber = 1/wavelength
wavelength = 253.4 nm

Z fro Be = 4

Therefore, the principal quantum number corresponding to the given emission is 4.
Answer: M = 0.036 M
Explanation: Solution attached:
First convert mass of NH3 to moles
Next convert volume in mL to L
Use the formula for Molarity
M = n / L
Answer:a weak acid and a weak base
Explanation: