The term formula units means molecules.
Then, what you are looking for is the mass in 4.59*10^24 molecules.
The procedure involves to convert the 4.59 * 10^24 molecules into moles and use the molar mass of the sodium chloride.
1) Number of moles = 4.59 * 10^24 molecules / (6.02 * 10^23 molecules/mol) = 7.62 mol
2) Molar mass of NaCl = 22.99 g/mol + 35.45 g/mol = 58.44 g/mol
3) mass of NaCl = molar mass * number of moles = 58.44 g/mol * 7.62 mol = 445.31 g of NaCl
Answer: 445.31 g of NaCl.
Answer:

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Answer:
Compound B is ionic. The electronegativity difference is 2.2, which can be determined by subtracting the electronegativity of Element Y from that of Element Z. Electronegativity differences greater than 1.7 indicate ionic bonds.
Hope that helps.
You take the moles divided by the liters to get the molarity.