<u>Answer:</u> The fraction of atom's mass contributed by nucleus is 0.99
<u>Explanation:</u>
Nucleons are defined as the sub-atomic particles which are present in the nucleus of an atom. Nucleons are protons and neutrons.
The isotopic symbol of Helium-4 atom is 
Number of electrons = 2
Number of protons = 2
Number of neutrons = 4 - 2 = 2
We are given:
Mass of He-4 atom = 
Mass of 1 electron = 
Calculating the mass contributed by the nucleus = 
Mass of the nucleus of He-4 atom = 
To calculate the fraction of atom's mass contributed by the nucleus, we use the equation:

Putting values in above equation, we get:

Hence, the fraction of atom's mass contributed by nucleus is 0.99
Answer:
(b) Calculate the molarity of a solution of 4.8 mole of HCl in 600 mL of solution. ... (g) Calculate the mass of Na2CO3 that must be used to make 700 mL of a 0.136 M Na2CO3 ... (h) What mass of NaOH is needed to make 200 mL of a 0.300 M NaOH solution? ... However, when we are reacting solutions we have to convert.
Explanation:
It addressed the problem concerning why electrons didn't fall into the positive nucleus. HOPE THIS HELPS BRAINLIEST PLEASE
The vapor pressure is obtained as 23.47 torr.
<h3>What is the vapor pressure?</h3>
Given that; p = x1p°
p = vapor pressure of the solution
x1 = mole fraction of the solvent
p° = vapor pressure of the pure solvent
Δp = p°(1 - x1)
Δp =x2p°
Δp = vapor pressure lowering
x2 = mole fraction of the of the solute
Number of moles of glycerol = 32.5 g/92 g/mol = 0.35 moles
Number of moles of water = 500.0 g/18 g/mol = 27.8 moles
Total number of moles = 0.35 moles + 27.8 moles = 28.15 moles
Mole fraction of glycerol = 0.35 moles/28.15 moles = 0.012
Mole fraction of water = 27.8 moles/28.15 moles =0.99
Δp = 0.012 * 23.76 torr
Δp = 0.285 torr
p1 = p° - Δp
p1 = 23.76 torr - 0.285 torr
p1 = 23.47 torr
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