Calculate the number of moles present in each of the following samples.6.684e13 pg of fluorine atoms 2.435e6 mg of magnesium 3.2e-3 kg of lead(II) chloride 6.684e-5 Mg of fluorine 2.31e-9 Gg of carbon disulfide 4.91e9 ng of aluminum sulfate?

Answer 1

umber of Moles=

Molar Mass (in g/mol)

Mass (in grams)

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First, you'll need to know the molar mass of the substance in question. Here are the calculations for each sample:

6.684e13 pg of fluorine atoms:

Molar mass of fluorine (F) = 19 g/mol

Mass in grams = 6.684e13 pg = 6.684e-6 g

Number of moles = (6.684e-6 g) / (19 g/mol) ≈ 3.52e-7 moles

2.435e6 mg of magnesium:

Molar mass of magnesium (Mg) = 24.305 g/mol

Mass in grams = 2.435e6 mg = 2.435 g

Number of moles = (2.435 g) / (24.305 g/mol) ≈ 0.1001 moles

3.2e-3 kg of lead(II) chloride:

Molar mass of lead(II) chloride (PbCl₂) = 207.2 g/mol

Mass in grams = 3.2e-3 kg = 3200 g

Number of moles = (3200 g) / (207.2 g/mol) ≈ 15.45 moles

6.684e-5 Mg of fluorine:

Molar mass of fluorine (F) = 19 g/mol

Mass in grams = 6.684e-5 Mg = 6.684e-5 g

Number of moles = (6.684e-5 g) / (19 g/mol) ≈ 3.52e-6 moles

2.31e-9 Gg of carbon disulfide:

Molar mass of carbon disulfide (CS₂) = 76.143 g/mol

Mass in grams = 2.31e-9 Gg = 2.31e15 g

Number of moles = (2.31e15 g) / (76.143 g/mol) ≈ 3.03e12 moles

4.91e9 ng of aluminum sulfate:

Molar mass of aluminum sulfate (Al₂(SO₄)₃) = 342.15 g/mol

Mass in grams = 4.91e9 ng = 4.91e-6 g

Number of moles = (4.91e-6 g) / (342.15 g/mol) ≈ 1.43e-8 moles