The moles can be defined as the mass of the substance with respect to molar mass. The moles of potassium nitrate is 1 mol.
<h3>How to calculate moles of a substance?</h3>
The moles of a compound can be calculated from:

The molarity can be defined as the moles of solute in a liter of solution.
The molarity can be expressed as:

The molarity of potassium nitrate solution is 2 M, and the volume is 500 mL.
The moles of potassium nitrate is given as:

The moles of potassium nitrate in 2 M, 500 mL solution are 1 mol.
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I think is 5 because you use density is found by mass divide by volume.
The correct answer is option 1. The mass of a proton is approximately equal to 1 atomic mass unit. They almost have the same mass with a<span> neutron </span>while the electron is about 2000 times lighter than the two. The three mentioned particles are the subatomic particles found in an atom.
The correct answer is D, they are reviewed by experts.
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