Calculating Gold Mass and Molarity

This video tutorial demonstrates how to solve an ALEKS problem involving the calculation of the molar mass of elements, specifically using gold as an example. The instructor guides viewers through setting up the problem, using conversion factors, and performing calculations to determine the mass of gold in grams. The video emphasizes the importance of using the correct periodic table to ensure accurate results and provides tips on handling significant figures.

What is the symbol for the element gold?

• Au

• Fe

• Ag

• Pb

What is the first step in solving the problem of calculating the mass of gold?

• Convert grams to moles

• Look up the atomic number

• Find the density of gold

• Write down the given quantity and its unit

When setting up the conversion factor, what should be placed at the bottom of the fraction?

• The atomic number

• The unit you are converting to

• The density of the element

• The unit you are converting from

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

• 197.0 g/mol

• 198.967 g/mol

• 195.084 g/mol

• 196.967 g/mol

How many significant figures should the final answer have?

• Three

• Two

• Four

• One

What is the final calculated mass of gold in grams?

• 9.0 grams

• 8.86 grams

• 8.8 grams

• 8.9 grams

What should you do if the third digit in your answer is 6?

• Leave it as is

• Add a zero

• Round up

• Round down

What is the relationship between grams and moles for gold?

• 200 grams per mole

• 100 grams per mole

• 1 gram per mole

• 196.967 grams per mole

Why is it important to use the periodic table provided by ALEKS?

• It ensures the mass values match the problem requirements

• It is more colorful

• It is easier to read

• It has the most recent data

What should you do if your periodic table has different mass values than ALEKS?

• Use your own values

• Ignore the difference

• Use ALEKS's values

• Average the two values