Mole Conversions and Molar Mass

The video tutorial covers proficiency number five, focusing on converting grams to moles. It begins with a lithium example, explaining the conversion process using the periodic table to find molar mass. The tutorial then moves to an iodine example, highlighting the need to consider diatomic molecules. Finally, it provides general tips for calculating molar mass and converting moles to grams, emphasizing the importance of significant figures.

What is the first step in converting grams to moles?

• Divide grams by the atomic mass

• Add grams to the atomic mass

• Multiply grams by the atomic mass

• Subtract grams from the atomic mass

How many grams does one mole of lithium weigh?

• 7.941 grams

• 6.941 grams

• 5.941 grams

• 8.941 grams

What is the result of converting 13 grams of lithium to moles?

• 1.67 moles

• 1.77 moles

• 1.97 moles

• 1.87 moles

Why do we need to consider the diatomic nature of iodine when converting I2 to moles?

• Because I2 is a compound

• Because I2 is heavier than I

• Because I2 is lighter than I

• Because I2 consists of two iodine atoms

What is the molar mass of I2?

• 253.8 grams

• 126.9 grams

• 200.0 grams

• 150.0 grams

How many moles are in 2.1 x 10^3 grams of I2?

• 8.47 moles

• 8.37 moles

• 8.27 moles

• 8.57 moles

What is the correct number of significant figures for the conversion of 2.1 x 10^3 grams of I2 to moles?

• Two significant figures

• Five significant figures

• Three significant figures

• Four significant figures

What is the general approach to converting from moles to grams?

• Add moles to the molar mass

• Divide moles by the molar mass

• Multiply moles by the molar mass

• Subtract moles from the molar mass

When converting compounds with multiple elements, what should you do?

• Divide the atomic masses of all elements

• Add up the atomic masses of all elements

• Subtract the atomic masses of all elements

• Multiply the atomic masses of all elements

What is the opposite process of converting grams to moles?

• Converting moles to grams

• Converting grams to liters

• Converting liters to moles

• Converting moles to liters