Conversions in Chemistry and Temperature

Mr. Olsen's chemistry tutorial covers conversions between grams, moles, and atoms using molar mass and Avogadro's number. Three sample problems are solved: converting moles of helium to grams, atoms of boron to moles, and grams of gold to atoms. A quick temperature conversion from Fahrenheit to Celsius is also demonstrated.

What is the molar mass of an element used for in conversions?

• To determine the number of atoms in a mole

• To convert grams to moles

• To calculate the density

• To find the atomic number

How many grams are in 3.88 moles of helium?

• 15.52 grams

• 18.44 grams

• 20.00 grams

• 12.32 grams

What is Avogadro's number used for?

• To find the atomic mass

• To convert moles to grams

• To convert atoms to moles

• To calculate the volume

How many moles are in 1.85 x 10^24 atoms of boron?

• 1.85 moles

• 4.00 moles

• 2.50 moles

• 3.08 moles

What is the first step in converting grams of gold to atoms?

• Convert moles to grams

• Convert atoms to moles

• Convert grams to moles

• Convert grams to atoms directly

How many atoms are in 39.5 grams of gold?

• 1.00 x 10^23 atoms

• 1.50 x 10^23 atoms

• 2.00 x 10^23 atoms

• 1.20 x 10^23 atoms

What is the molar mass of gold used in the conversion?

• 197.0 grams/mole

• 196.0 grams/mole

• 195.0 grams/mole

• 198.0 grams/mole

What is the formula to convert Fahrenheit to Celsius?

• C = (F - 32) x 5/9

• C = (F + 32) x 9/5

• C = (F + 32) x 5/9

• C = (F - 32) x 9/5

What is the first step in converting Fahrenheit to Celsius?

• Multiply by 9/5

• Subtract 32

• Add 32

• Multiply by 5/9

What is the final step in converting Fahrenheit to Celsius?

• Add 32

• Multiply by 9/5

• Multiply by 5/9

• Subtract 32