Counting Units and the Mole

In chemistry, the mole is . . .

• a really big number that does change

• a really big number that does not change

• a furry creature that lives underground

• a really small number

How many are in 3.5 dozen?

• 12

• 24

• 30

• 36

• 42

Which number is bigger?

(1 ream = 500; 1 gross = 144)

• 2 reams

• 2 gross

• 800

• 300

Which number is bigger?

• 2 trillion

• 2 moles

• 1,000,000 billion

A baker has 54 donuts. How many dozens of donuts does the baker have?

• 2 dozen

• 4 dozen

• 4.5 dozen

• 648 dozen

How many total molecules are in 3.25 moles?

(Select the answer that is in correct scientific notation)

• 19.565 × 10²³

• 1.9565 × 10²⁴

• 19.565

• 1.9565 × 10²²

A chemist has 0.01 moles of carbon atoms. How many carbon atoms does the chemist have?

(Select the answer that is in correct scientific notation)

• 6.02 × 10²¹

• 0.0602 × 10²³

• 0.0602

• 6.02 × 10²²

• 0.602 × 10²²

Foothill's graphics center uses 8,500 sheets of paper per day. How many reams of paper is this?

(1 ream = 500 sheets)

• 17 reams

• 10 reams

• 0.05 reams

• 8.5 reams

Dr. May has 2.107 × 10²³ atoms of silver. How many moles of silver does Dr. May have?

(Hint: use division)

• 0.35 moles

• 2.86 moles

• 12.68 moles

• 2 moles

Dr. May has 4.816 × 10²⁴ atoms of gold. How many moles of gold does Dr. May have?

(Hint: use division)

• 8 moles

• 0.8 moles

• 28.992 moles

• 6 moles