CHEM 1311-07P (09/28)

How many moles of Cobalt (Co) atoms are there in 6.00 x 10^9 (6 billion) Co atoms?

• 9.96 x 10^15

• 9.96 x 10^-15

• 6.89 x 10^-15

• 6.89 x 10^15

How many atoms are there in 5.10 moles of sulfur (S)?

• 6.022 x 10^23 atom

• 3.071 x 10^23 atom

• 3.117 x 10^23 atom

• 3.071 x 10^24 atom

How many moles of Calcium (Ca) are in 77.4 g of Ca?

• 2.872 mol

• 1.931 mol

• 1.471 x 10^23 mol

• 1.876 mol

How many grams of gold (Au) are there in 15.3 moles of Au?

• 2012.21 g

• 101.2 g

• 3013.48 g

• 6.022 x 10^23 g

What is the mass in grams of a single atom of Si?

• 3.23 x 10^-22

• 4.66 x 10^-23

• 4.03 x 10^-22

• 2.01 x 10^-23

What is the mass in grams of 1.00 x 10^12 lead (Pb) atoms?

• 4.43 x 10^10 g

• 3.34 x 10^-10 g

• 3.44 x 10^-10 g

• 3.22 x 10^-10 g

How many atoms are present in 25.85 g of copper (Cu)?

• 1.45 x 10^23

• 2.45 x 10^23

• 1.23 x 10^23

• 2.34 x 10^23

Calculate the molar mass of each substance: Li2Co3 and CS2

• 131.07 Li2CO3, 79.22 CS2

• 93.21 Li2CO3, 76.139 CS2

• 73.89 Li2CO3, 72.20 CS2

• 73.89 Li2CO3, 76.139 CS2

How many molecules of ethane (C2H6) are present in 0.334 g of C2H6?

• 7.45 x 10^-21

• 7.45 x 10^21

• 6.89 x 10^21

• 6.89 x 10^-21

Calculate the number of C atoms in 1.5 g of glucose (C6H12O6), a sugar.

• 1.20 x 10^23 atoms

• 1.29 x 10^23 atoms

• 2.03 x 10^23 atoms

• 3.01 x 10^23 atoms