Mastering Mole Conversions in Chemistry

Mrs. Bodachon guides students through stoichiometry conversions, including moles to molecules, molecules to moles, moles to grams, and grams to moles. She emphasizes the use of Avogadro's number and molar mass, providing calculator tips for accurate calculations. The tutorial covers sulfur dioxide and iron conversions, with practical examples to ensure understanding before quizzes or tests.

What is the first step in solving a stoichiometry problem?

• Start with what you know.

• Start with the conversion factor.

• Start with what you want to find.

• Start with the periodic table.

How many molecules are in 2.5 moles of SO2?

• 1.5 x 10^24

• 6.022 x 10^23

• 3.01 x 10^23

• 2.5 x 10^24

What is Avogadro's number?

• 1.5 x 10^24

• 2.5 x 10^24

• 3.01 x 10^23

• 6.022 x 10^23

How do you convert molecules to moles?

• Multiply by the molar mass.

• Divide by Avogadro's number.

• Multiply by Avogadro's number.

• Divide by the molar mass.

How many moles are in 3.01 x 10^23 molecules of SO2?

• 1.5 moles

• 0.602 moles

• 0.301 moles

• 0.499 moles

What is the molar mass of iron (Fe) used in the video?

• 56.845 g/mol

• 55.845 g/mol

• 40.078 g/mol

• 55.85 g/mol

How many grams are in 3.8 moles of iron (Fe)?

• 211.21 grams

• 210.21 grams

• 212.21 grams

• 213.21 grams

What is the molar mass of calcium (Ca) used in the video?

• 40.078 g/mol

• 55.845 g/mol

• 55.85 g/mol

• 40.078 g

How many moles are in 20 grams of calcium (Ca)?

• 0.49 moles

• 0.50 moles

• 0.48 moles

• 0.51 moles

What is a helpful tip when using a scientific calculator for stoichiometry problems?

• Use the sine function.

• Use the square root function.

• Use parentheses for Avogadro's number.

• Use the logarithm function.