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The molecular weight of table salt, NaCl, is 58.5 g/mol. A tablespoon of salt weighs 6.37 grams. Calculate the number of moles of salt in one tablespoon. Next, cancel like terms and units: Which of the following shows the correct terms and units canceled?

A>N>S: the 2nd one

User Adam Sills
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Final answer:

To calculate the number of moles of table salt (NaCl) in a tablespoon weighing 6.37 grams, divide the mass by the molecular weight of NaCl (58.44 g/mol), which gives approximately 0.109 moles. In the cancellation step, grams cancel out, leaving the unit 'mol' for moles.

Step-by-step explanation:

The student has asked how to calculate the number of moles of table salt (NaCl) in one tablespoon, given that the molecular weight of NaCl is 58.5 g/mol and a tablespoon of salt weighs 6.37 grams. To find the number of moles, use the formula:

Number of moles = mass (in grams) ÷ molar mass (in g/mol)

Substituting the given values, we get:

Number of moles = 6.37 g ÷ 58.44 g/mol

The correct calculation is (6.37 g)/(58.44 g/mol) which equals approximately 0.109 moles of NaCl.

The units grams (g) cancel out, leaving the units in moles (mol) as desired. The molecular weight and the mass of the NaCl are both in grams, so when dividing these two values, grams cancel out, and you're left with the unit 'mol' for moles.

User Luiz Avila
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